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NAME

       gmpy2 - gmpy2 Documentation

       Contents:

INTRODUCTION TO GMPY2

       gmpy2  is  a  C-coded Python extension module that supports multiple-precision arithmetic.
       gmpy2 is the successor to the original gmpy module. The gmpy module only supported the GMP
       multiple-precision  library.  gmpy2  adds  support  for  the  MPFR (correctly rounded real
       floating-point arithmetic) and MPC (correctly rounded complex  floating-point  arithmetic)
       libraries.  gmpy2  also  updates  the API and naming conventions to be more consistent and
       support the additional functionality.

       The following libraries are supported:

       • GMP for integer and rational arithmetic

         Home page: http://gmplib.org

       • MPIR is based on the  GMP  library  but  adds  support  for  Microsoft's  Visual  Studio
         compiler. It is used to create the Windows binaries.

         Home page: http://www.mpir.org

       • MPFR for correctly rounded real floating-point arithmetic

         Home page: http://www.mpfr.org

       • MPC for correctly rounded complex floating-point arithmetic

         Home page: http://mpc.multiprecision.org

       • Generalized Lucas sequences and primality tests are based on the following code:

         mpz_lucas: http://sourceforge.net/projects/mpzlucas/

         mpz_prp: http://sourceforge.net/projects/mpzprp/

   gmpy2 Versions
       This  manual  documents  the  two major versions of gmpy2. Sections that are specific to a
       particular version will be identified as such.

       The 2.0 version is the stable release that only receives bug fixes and very minor updates.
       Version  2.1  is currently under active development and includes several new capabilities.
       Most gmpy2 2.0 code should run unchanged with gmpy2 2.1.

       The most significant change in gmpy2 2.1 is support for thread-safe contexts.  This change
       required extensive refactoring of almost all internal functions.

       Please see the History chapter for a detail list of the changes.

INSTALLATION

   Installing gmpy2 on Windows
       Pre-compiled versions of gmpy2 2.0.8 are available at https://pypi.org/project/gmpy2/.

       A      pre-compiled      version      of     gmpy2     2.1.0a1     is     available     at
       https://pypi.org/project/gmpy2/2.1.0a1/. Updated  Windows  versions  should  be  available
       again beginning with version 2.1.0b1.

   Installing gmpy2 on Unix/Linux
   Requirements
       gmpy2  has  only  been  tested  with  the  most  recent  versions  of  GMP,  MPFR and MPC.
       Specifically, for integer and rational support, gmpy2 requires  GMP  5.0.x  or  later.  To
       support multiple-precision floating point arithmetic, MPFR 3.1.x or later is required. MPC
       1.0.1 or later is required for complex arithmetic.

   Short Instructions
       gmpy2 requires the development files for GMP, MPFR,  and  MPC.  The  actual  package  that
       provides  these  files varies between Linux distributions. Installing "libmpc-dev" (or its
       equivalent) is usually sufficient.

       If your system has the development libraries installed, compiling should be as simple as:

          cd <gmpy2 source directory>
          python setup.py build_ext --force install --force

       If this fails, read on.

   Detailed Instructions
       Note: You really shouldn't need to do this. Unless you need the  capabilities  provided  a
       newer GMP/MPFR/MPC, you should use the versions provided by your distribution.

       If your Linux distribution does not support recent versions of GMP, MPFR and MPC, you will
       need to compile your own versions. To avoid any possible conflict with existing  libraries
       on  your  system,  it  is  recommended  to  use  a  directory  not  normally  used by your
       distribution.

       Create the desired destination directory for GMP, MPFR, and MPC.

          $ mkdir /home/<<your username>>/local

       Download and un-tar the GMP source code. Change to the GMP source  directory  and  compile
       GMP.

          $ cd /home/<<your username>>/local/src/gmp-6.1.2
          $ ./configure --prefix=/home/<<your username>>/local
          $ make
          $ make check
          $ make install

       Download  and un-tar the MPFR source code. Change to the MPFR source directory and compile
       MPFR.

          $ cd /home/<<your username>>/local/src/mpfr-4.0.1
          $ ./configure --prefix=/home/<<your username>>/local --with-gmp=/home/<<your username>>/local
          $ make
          $ make check
          $ make install

       Download and un-tar the MPC source code. Change to the MPC source  directory  and  compile
       MPC.

          $ cd /home/<<your username>>/local/src/mpc-1.1.0
          $ ./configure --prefix=/home/<<your username>>/local --with-gmp=/home/<<your username>>/local --with-mpfr=/home/<<your username>>/local
          $ make
          $ make check
          $ make install

       Compile  gmpy2  and  specify  the  location of GMP, MPFR and MPC. The location of the GMP,
       MPFR, and MPC libraries is embedded into the gmpy2 library so the  new  versions  of  GMP,
       MPFR,  and  MPC  do  not  need  to be installed the system library directories. The prefix
       directory is added to the beginning of the directories that are  checked  so  it  will  be
       found first.

          $ python setup.py install --prefix=/home/case/local

       If you get a "permission denied" error message, you may need to use:

          $ python setup.py build --prefix=/home/case/local
          $ sudo python setup.py install --prefix=/home/case/local

   Options for setup.py
       --force
              Ignore  the  timestamps  on  all  files  and  recompile. Normally, the results of a
              previous compile are cached. To force gmpy2 to recognize external changes  (updated
              version of GMP, etc.), you will need to use this option.

       --mpir Force  the  use  of  MPIR instead of GMP. GMP is the default library on non-Windows
              operating systems.

       --gmp  Force the use of GMP instead of MPIR.  MPIR  is  the  default  library  on  Windows
              operating systems.

       --shared=<...>
              Add the specified directory prefix to the beginning of the list of directories that
              are searched for GMP, MPFR, and MPC shared libraries.

       --static=<...>
              Create a statically linked library using libraries from the specified path, or from
              the operating system's default library location if no path is specified

OVERVIEW OF GMPY2

   Tutorial
       The  mpz  type  is  compatible  with  Python's built-in int/long type but is significantly
       faster for large values. The cutover point for performance varies, but can be as low as 20
       to 40 digits. A variety of additional integer functions are provided.

          >>> import gmpy2
          >>> from gmpy2 import mpz,mpq,mpfr,mpc
          >>> mpz(99) * 43
          mpz(4257)
          >>> pow(mpz(99), 37, 59)
          mpz(18)
          >>> gmpy2.isqrt(99)
          mpz(9)
          >>> gmpy2.isqrt_rem(99)
          (mpz(9), mpz(18))
          >>> gmpy2.gcd(123,27)
          mpz(3)
          >>> gmpy2.lcm(123,27)
          mpz(1107)

       The mpq type is compatible with the fractions.Fraction type included with Python.

          >>> mpq(3,7)/7
          mpq(3,49)
          >>> mpq(45,3) * mpq(11,8)
          mpq(165,8)

       The  most  significant  new  features in gmpy2 are support for correctly rounded arbitrary
       precision real and complex arithmetic based on the MPFR and MPC libraries. Floating  point
       contexts  are  used  to control exceptional conditions.  For example, division by zero can
       either return an Infinity or raise an exception.

          >>> mpfr(1)/7
          mpfr('0.14285714285714285')
          >>> gmpy2.get_context().precision=200
          >>> mpfr(1)/7
          mpfr('0.1428571428571428571428571428571428571428571428571428571428571',200)
          >>> gmpy2.get_context()
          context(precision=200, real_prec=Default, imag_prec=Default,
                  round=RoundToNearest, real_round=Default, imag_round=Default,
                  emax=1073741823, emin=-1073741823,
                  subnormalize=False,
                  trap_underflow=False, underflow=False,
                  trap_overflow=False, overflow=False,
                  trap_inexact=False, inexact=True,
                  trap_invalid=False, invalid=False,
                  trap_erange=False, erange=False,
                  trap_divzero=False, divzero=False,
                  trap_expbound=False,
                  allow_complex=False)
          >>> mpfr(1)/0
          mpfr('inf')
          >>> gmpy2.get_context().trap_divzero=True
          >>> mpfr(1)/0
          Traceback (most recent call last):
            File "<stdin>", line 1, in <module>
          gmpy2.DivisionByZeroError: 'mpfr' division by zero in division
          >>> gmpy2.get_context()
          context(precision=200, real_prec=Default, imag_prec=Default,
                  round=RoundToNearest, real_round=Default, imag_round=Default,
                  emax=1073741823, emin=-1073741823,
                  subnormalize=False,
                  trap_underflow=False, underflow=False,
                  trap_overflow=False, overflow=False,
                  trap_inexact=False, inexact=True,
                  trap_invalid=False, invalid=False,
                  trap_erange=False, erange=False,
                  trap_divzero=True, divzero=True,
                  trap_expbound=False,
                  allow_complex=False)
          >>> gmpy2.sqrt(mpfr(-2))
          mpfr('nan')
          >>> gmpy2.get_context().allow_complex=True
          >>> gmpy2.get_context().precision=53
          >>> gmpy2.sqrt(mpfr(-2))
          mpc('0.0+1.4142135623730951j')
          >>>
          >>> gmpy2.set_context(gmpy2.context())
          >>> with gmpy2.local_context() as ctx:
          ...   print(gmpy2.const_pi())
          ...   ctx.precision+=20
          ...   print(gmpy2.const_pi())
          ...   ctx.precision+=20
          ...   print(gmpy2.const_pi())
          ...
          3.1415926535897931
          3.1415926535897932384628
          3.1415926535897932384626433831
          >>> print(gmpy2.const_pi())
          3.1415926535897931
          >>>

   Miscellaneous gmpy2 Functions
       from_binary(...)
              from_binary(bytes)  returns  a  gmpy2  object  from  a  byte  sequence  created  by
              to_binary().

       get_cache(...)
              get_cache() returns the current cache size (number of objects) and the maximum size
              per object (number of limbs).

              gmpy2 maintains an internal list of freed mpz, xmpz, mpq, mpfr, and mpc objects for
              reuse.  The  cache significantly improves performance but also increases the memory
              footprint.

       license(...)
              license() returns the gmpy2 license information.

       mp_limbsize(...)
              mp_limbsize() returns the number of bits per limb used by the GMP or MPIR library.

       mp_version(...)
              mp_version() returns the version of the GMP or MPIR library.

       mpc_version(...)
              mpc_version() returns the version of the MPC library.

       mpfr_version(...)
              mpfr_version() returns the version of the MPFR library.

       random_state(...)
              random_state([seed]) returns a new object  containing  state  information  for  the
              random  number generator. An optional integer argument can be specified as the seed
              value. Only the Mersenne Twister random number generator is supported.

       set_cache(...)
              set_cache(number, size) updates the maximum number of freed objects  of  each  type
              that  are cached and the maximum size (in limbs) of each object. The maximum number
              of objects of each type that can be cached is 1000. The maximum size of  an  object
              is  16384. The maximum size of an object is approximately 64K on 32-bit systems and
              128K on 64-bit systems.

              NOTE:
                 The caching options are global to gmpy2. Changes are not thread-safe.  A  change
                 in one thread will impact all threads.

       to_binary(...)
              to_binary(x)  returns  a  byte  sequence  from a gmpy2 object. All object types are
              supported.

       version(...)
              version() returns the version of gmpy2.

MULTIPLE-PRECISION INTEGERS

       The gmpy2 mpz  type  supports  arbitrary  precision  integers.  It  should  be  a  drop-in
       replacement  for Python's long type. Depending on the platform and the specific operation,
       an mpz will be faster than Python's long once the precision exceeds 20 to 50  digits.  All
       the special integer functions in GMP are supported.

   Examples
          >>> import gmpy2
          >>> from gmpy2 import mpz
          >>> mpz('123') + 1
          mpz(124)
          >>> 10 - mpz(1)
          mpz(9)
          >>> gmpy2.is_prime(17)
          True

       NOTE:
          The  use of from gmpy2 import * is not recommended. The names in gmpy2 have been chosen
          to avoid conflict with Python's builtin  names  but  gmpy2  does  use  names  that  may
          conflict with other modules or variable names.

   mpz Methods
       bit_clear(...)
              x.bit_clear(n) returns a copy of x with bit n set to 0.

       bit_flip(...)
              x.bit_flip(n) returns a copy of x with bit n inverted.

       bit_length(...)
              x.bit_length() returns the number of significant bits in the radix-2 representation
              of x. For compatibility with Python, mpz(0).bit_length() returns 0.

       bit_scan0(...)
              x.bit_scan0(n) returns the index of the first 0-bit of x with index >= n. If  there
              are  no  more  0-bits  in  x  at or above index n (which can only happen for x < 0,
              assuming an infinitely long 2's complement format), then None is returned.  n  must
              be >= 0.

       bit_scan1(...)
              x.bit_scan1(n)  returns the index of the first 1-bit of x with index >= n. If there
              are no more 1-bits in x at or above index n (which can only  happen  for  x  >=  0,
              assuming  an  infinitely long 2's complement format), then None is returned. n must
              be >= 0.

       bit_set(...)
              x.bit_set(n) returns a copy of x with bit n set to 1.

       bit_test(...)
              x.bit_test(n) returns True if bit n of x is set, and False if it is not set.

       conjugtae(...)
              Return the conjugate of x (which is just a new reference to x since x not a complex
              number).

       denominator(...)
              x.denominator() returns mpz(1).

       digits(...)
              x.digits([base=10]) returns a string representing x in radix base.

       imag   Return the imaginary component of an mpz. Always mpz(0).

       is_congruent(...)
              x.is_congruent(y,  m)  returns  True  if x is congruent to y modulo m, else returns
              False.

       is_divisible(...)
              x.is_divisible(d) returns True if x is divisible by d, else returns False.

       is_even(...)
              x.is_even() returns True if x is even, else returns False.

       is_odd(...)
              x.is_odd() returns True if x is even, else returns False.

       is_power(...)
              x.is_power() returns True if x is a perfect power (there exists integers y and n  >
              1, such that x=y**n), else returns False.

       is_prime(...)
              x.is_prime()  returns  True if x is _probably_ prime, else False if x is definitely
              composite.

              See the documentation for gmpy2.is_prime for details on the  underlaying  primality
              tests that are performed.

       is_square(...)
              x.is_square() returns True if x is a perfect square, else returns False.

       num_digits(...)
              x.num_digits([base=10])  returns the length of the string representing the absolute
              value of x in radix base. The result is correct if base is a power of 2. For  other
              bases, the result is usually correct but may be 1 too large. base can range between
              2 and 62, inclusive.

       numerator(...)
              x.numerator() returns a copy of x.

       real(...)
              x.real returns a copy of x.

   mpz Functions
       add(...)
              add(x, y) returns x + y. The result type depends on the input types.

       bincoef(...)
              bincoef(x, n) returns the binomial coefficient. n must be >= 0.

       bit_clear(...)
              bit_clear(x, n) returns a copy of x with bit n set to 0.

       bit_flip(...)
              bit_flip(x, n) returns a copy of x with bit n inverted.

       bit_length(...)
              bit_length(x) returns the number of significant bits in the radix-2  representation
              of   x.   For  compatibility  with  Python,  mpz(0).bit_length()  returns  0  while
              mpz(0).num_digits(2) returns 1.

       bit_mask(...)
              bit_mask(n) returns an mpz object exactly n bits in length with all bits set.

       bit_scan0(...)
              bit_scan0(x, n) returns the index of the first 0-bit of x with index >= n. If there
              are  no  more  0-bits  in  x  at or above index n (which can only happen for x < 0,
              assuming an infinitely long 2's complement format), then None is returned.  n  must
              be >= 0.

       bit_scan1(...)
              bit_scan1(x, n) returns the index of the first 1-bit of x with index >= n. If there
              are no more 1-bits in x at or above index n (which can only  happen  for  x  >=  0,
              assuming  an  infinitely long 2's complement format), then None is returned. n must
              be >= 0.

       bit_set(...)
              bit_set(x, n) returns a copy of x with bit n set to 1.

       bit_test(...)
              bit_test(x, n) returns True if bit n of x is set, and False if it is not set.

       c_div(...)
              c_div(x, y) returns the quotient of x divided by y. The quotient is rounded towards
              +Inf (ceiling rounding). x and y must be integers.

       c_div_2exp(...)
              c_div_2exp(x, n) returns the quotient of x divided by 2**n. The quotient is rounded
              towards +Inf (ceiling rounding). x must be an integer and n must be > 0.

       c_divmod(...)
              c_divmod(x, y) returns the quotient and remainder of x divided by y.  The  quotient
              is rounded towards +Inf (ceiling rounding) and the remainder will have the opposite
              sign of y. x and y must be integers.

       c_divmod_2exp(...)
              c_divmod_2exp(x ,n) returns the quotient and remainder of x divided  by  2**n.  The
              quotient  is  rounded  towards  +Inf  (ceiling  rounding) and the remainder will be
              negative or zero. x must be an integer and n must be > 0.

       c_mod(...)
              c_mod(x, y) returns the remainder of x divided by y. The remainder  will  have  the
              opposite sign of y. x and y must be integers.

       c_mod_2exp(...)
              c_mod_2exp(x,  n) returns the remainder of x divided by 2**n. The remainder will be
              negative. x must be an integer and n must be > 0.

       comb(...)
              comb(x, n) returns the number of combinations of x things, taking n at  a  time.  n
              must be >= 0.

       digits(...)
              digits(x[, base=10]) returns a string representing x in radix base.

       div(...)
              div(x, y) returns x / y. The result type depends on the input types.

       divexact(...)
              divexact(x,  y)  returns  the  quotient  of  x  divided  by y. Faster than standard
              division but requires the remainder is zero!

       divm(...)
              divm(a, b, m) returns x such that b * x == a modulo m. Raises  a  ZeroDivisionError
              exception if no such value x exists.

       f_div(...)
              f_div(x, y) returns the quotient of x divided by y. The quotient is rounded towards
              -Inf (floor rounding). x and y must be integers.

       f_div_2exp(...)
              f_div_2exp(x, n) returns the quotient of x divided by 2**n. The quotient is rounded
              towards -Inf (floor rounding). x must be an integer and n must be > 0.

       f_divmod(...)
              f_divmod(x,  y)  returns the quotient and remainder of x divided by y. The quotient
              is rounded towards -Inf (floor rounding) and the remainder will have the same  sign
              as y. x and y must be integers.

       f_divmod_2exp(...)
              f_divmod_2exp(x,  n)  returns  quotient and remainder after dividing x by 2**n. The
              quotient is rounded towards  -Inf  (floor  rounding)  and  the  remainder  will  be
              positive. x must be an integer and n must be > 0.

       f_mod(...)
              f_mod(x,  y)  returns  the remainder of x divided by y. The remainder will have the
              same sign as y. x and y must be integers.

       f_mod_2exp(...)
              f_mod_2exp(x, n) returns remainder of x divided by  2**n.  The  remainder  will  be
              positive. x must be an integer and n must be > 0.

       fac(...)
              fac(n)  returns the exact factorial of n. Use factorial() to get the floating-point
              approximation.

       fib(...)
              fib(n) returns the n-th Fibonacci number.

       fib2(...)
              fib2(n) returns a 2-tuple with the (n-1)-th and n-th Fibonacci numbers.

       gcd(...)
              gcd(a, b) returns the greatest common divisor of integers a and b.

       gcdext(...)
              gcdext(a, b) returns a 3-element tuple (g, s, t) such that

              g == gcd(a, b) and g == a * s  + b * t

       hamdist(...)
              hamdist(x, y) returns the Hamming distance (number of bit-positions where the  bits
              differ) between integers x and y.

       invert(...)
              invert(x, m) returns y such that x * y == 1 modulo m, or 0 if no such y exists.

       iroot(...)
              iroot(x,n) returns a 2-element tuple (y, b) such that y is the integer n-th root of
              x and b is True if the root is exact. x must be >= 0 and n must be > 0.

       iroot_rem(...)
              iroot_rem(x,n) returns a 2-element tuple (y, r) such that y  is  the  integer  n-th
              root of x and x = y**n + r. x must be >= 0 and n must be > 0.

       is_even(...)
              is_even(x) returns True if x is even, False otherwise.

       is_odd(...)
              is_odd(x) returns True if x is odd, False otherwise.

       is_power(...)
              is_power(x) returns True if x is a perfect power, False otherwise.

       is_prime(...)
              is_prime(x[,  n=25]) returns True if x is probably prime. False is returned if x is
              definitely composite. x is checked for small divisors  and  up  to  n  Miller-Rabin
              tests are performed. The actual tests performed may vary based on version of GMP or
              MPIR used.

       is_square(...)
              is_square(x) returns True if x is a perfect square, False otherwise.

       isqrt(...)
              isqrt(x) returns the integer square root of an integer x. x must be >= 0.

       isqrt_rem(...)
              isqrt_rem(x) returns a 2-tuple (s, t) such that s = isqrt(x) and t = x - s *  s.  x
              must be >= 0.

       jacobi(...)
              jacobi(x, y) returns the Jacobi symbol (x | y). y must be odd and > 0.

       kronecker(...)
              kronecker(x, y) returns the Kronecker-Jacobi symbol (x | y).

       lcm(...)
              lcm(a, b) returns the lowest common multiple of integers a and b.

       legendre(...)
              legendre(x,  y)  returns  the  Legendre  symbol  (x | y). y is assumed to be an odd
              prime.

       lucas(...)
              lucas(n) returns the n-th Lucas number.

       lucas2(...)
              lucas2(n) returns a 2-tuple with the (n-1)-th and n-th Lucas numbers.

       mpz(...)
              mpz() returns a new mpz object set to 0.

              mpz(n) returns a new mpz object from a numeric value n. If n is not an integer,  it
              will be truncated to an integer.

              mpz(s[,  base=0])  returns  a  new mpz object from a string s made of digits in the
              given base. If base = 0, then binary, octal, or hex Python strings  are  recognized
              by leading 0b, 0o, or 0x characters. Otherwise the string is assumed to be decimal.
              Values for base can range between 2 and 62.

       mpz_random(...)
              mpz_random(random_state, n) returns a uniformly distributed random integer  between
              0 and n-1. The parameter random_state must be created by random_state() first.

       mpz_rrandomb(...)
              mpz_rrandomb(random_state,  b) returns a random integer between 0 and 2**b - 1 with
              long sequences of zeros and  one  in  its  binary  representation.   The  parameter
              random_state must be created by random_state() first.

       mpz_urandomb(...)
              mpz_urandomb(random_state,  b)  returns  a  uniformly  distributed  random  integer
              between  0  and  2**b  -  1.  The  parameter  random_state  must  be   created   by
              random_state() first.

       mul(...)
              mul(x, y) returns x * y. The result type depends on the input types.

       next_prime(...)
              next_prime(x) returns the next probable prime number > x.

       num_digits(...)
              num_digits(x[, base=10]) returns the length of the string representing the absolute
              value of x in radix base. The result is correct if base is a power of 2. For  other
              bases, the result is usually correct but may be 1 too large. base can range between
              2 and 62, inclusive.

       popcount(...)
              popcount(x) returns the number of bits with value 1 in x. If x < 0, the  number  of
              bits with value 1 is infinite so -1 is returned in that case.

       powmod(...)
              powmod(x,  y,  m)  returns  (x ** y) mod m. The exponent y can be negative, and the
              correct result will be returned if the inverse of x  mod  m  exists.  Otherwise,  a
              ValueError is raised.

       remove(...)
              remove(x, f) will remove the factor f from x as many times as possible and return a
              2-tuple (y, m) where y = x // (f ** m). f does not divide y. m is the  multiplicity
              of the factor f in x. f must be > 1.

       sub(...)
              sub(x, y) returns x - y. The result type depends on the input types.

       t_div(...)
              t_div(x, y) returns the quotient of x divided by y. The quotient is rounded towards
              zero (truncation). x and y must be integers.

       t_div_2exp(...)
              t_div_2exp(x, n) returns the quotient of x divided by 2**n. The quotient is rounded
              towards zero (truncation). n must be > 0.

       t_divmod(...)
              t_divmod(x,  y)  returns the quotient and remainder of x divided by y. The quotient
              is rounded towards zero (truncation) and the remainder will have the same  sign  as
              x. x and y must be integers.

       t_divmod_2exp(...)
              t_divmod_2exp(x,  n)  returns  the quotient and remainder of x divided by 2**n. The
              quotient is rounded towards zero (truncation) and the remainder will have the  same
              sign as x. x must be an integer and n must be > 0.

       t_mod(...)
              t_mod(x,  y)  returns  the remainder of x divided by y. The remainder will have the
              same sign as x. x and y must be integers.

       t_mod_2exp(...)
              t_mod_2exp(x, n) returns the remainder of x divided by  2**n.  The  remainder  will
              have the same sign as x. x must be an integer and n must be > 0.

MULTIPLE-PRECISION INTEGERS (ADVANCED TOPICS)

   The xmpz type
       gmpy2  provides  access  to  an  experimental integer type called xmpz. The xmpz type is a
       mutable integer type. In-place operations (+=, //=, etc.)  modify the original object  and
       do not create a new object. Instances of xmpz cannot be used as dictionary keys.

          >>> import gmpy2
          >>> from gmpy2 import xmpz
          >>> a = xmpz(123)
          >>> b = a
          >>> a += 1
          >>> a
          xmpz(124)
          >>> b
          xmpz(124)

       The  ability  to  change  an  xmpz  object  in-place  allows  for  efficient and rapid bit
       manipulation.

       Individual bits can be set or cleared:

          >>> a[10]=1
          >>> a
          xmpz(1148)

       Slice notation is supported. The bits referenced by a slice can be either 'read  from'  or
       'written  to'. To clear a slice of bits, use a source value of 0. In 2s-complement format,
       0 is represented by an arbitrary number of 0-bits. To set a slice of bits,  use  a  source
       value  of ~0. The tilde operator inverts, or complements the bits in an integer. (~0 is -1
       so you can also use -1.) In 2s-complement format, -1 is represented by an arbitrary number
       of 1-bits.

       If  a  value  for stop is specified in a slice assignment and the actual bit-length of the
       xmpz is less than stop, then the destination xmpz  is  logically  padded  with  0-bits  to
       length stop.

          >>> a=xmpz(0)
          >>> a[8:16] = ~0
          >>> bin(a)
          '0b1111111100000000'
          >>> a[4:12] = ~a[4:12]
          >>> bin(a)
          '0b1111000011110000'

       Bits can be reversed:

          >>> bin(a)
          '0b10001111100'
          >>> a[::] = a[::-1]
          >>> bin(a)
          '0b111110001'

       The  iter_bits()  method  returns  a  generator  that  returns  True or False for each bit
       position. The methods iter_clear(), and iter_set() return generators that return  the  bit
       positions  that  are  1 or 0. The methods support arguments start and stop that define the
       beginning and ending bit positions that are used. To mimic the behavior of slices. the bit
       positions checked include start but the last position checked is stop - 1.

          >>> a=xmpz(117)
          >>> bin(a)
          '0b1110101'
          >>> list(a.iter_bits())
          [True, False, True, False, True, True, True]
          >>> list(a.iter_clear())
          [1, 3]
          >>> list(a.iter_set())
          [0, 2, 4, 5, 6]
          >>> list(a.iter_bits(stop=12))
          [True, False, True, False, True, True, True, False, False, False, False, False]

       The following program uses the Sieve of Eratosthenes to generate a list of prime numbers.

          from __future__ import print_function
          import time
          import gmpy2

          def sieve(limit=1000000):
              '''Returns a generator that yields the prime numbers up to limit.'''

              # Increment by 1 to account for the fact that slices  do not include
              # the last index value but we do want to include the last value for
              # calculating a list of primes.
              sieve_limit = gmpy2.isqrt(limit) + 1
              limit += 1

              # Mark bit positions 0 and 1 as not prime.
              bitmap = gmpy2.xmpz(3)

              # Process 2 separately. This allows us to use p+p for the step size
              # when sieving the remaining primes.
              bitmap[4 : limit : 2] = -1

              # Sieve the remaining primes.
              for p in bitmap.iter_clear(3, sieve_limit):
                  bitmap[p*p : limit : p+p] = -1

              return bitmap.iter_clear(2, limit)

          if __name__ == "__main__":
              start = time.time()
              result = list(sieve())
              print(time.time() - start)
              print(len(result))

   Advanced Number Theory Functions
       The following functions are based on mpz_lucas.c and mpz_prp.c by David Cleaver.

       A good reference for probable prime testing is http://www.pseudoprime.com/pseudo.html

       is_bpsw_prp(...)
              is_bpsw_prp(n)  will  return  True  if  n is a Baillie-Pomerance-Selfridge-Wagstaff
              probable prime. A BPSW probable prime passes the is_strong_prp() test with  base  2
              and the is_selfridge_prp() test.

       is_euler_prp(...)
              is_euler_prp(n,a)   will   return   True   if   n   is  an  Euler  (also  known  as
              Solovay-Strassen) probable prime to the base a.
              Assuming:
                gcd(n, a) == 1
                n is odd

              Then an Euler probable prime requires:
                a**((n-1)/2) == 1 (mod n)

       is_extra_strong_lucas_prp(...)
              is_extra_strong_lucas_prp(n,p) will return True if  n  is  an  extra  strong  Lucas
              probable prime with parameters (p,1).
              Assuming:
                n is odd
                D = p*p - 4, D != 0
                gcd(n, 2*D) == 1
                n = s*(2**r) + Jacobi(D,n), s odd

              Then an extra strong Lucas probable prime requires:
                lucasu(p,1,s) == 0 (mod n)
                  or
                lucasv(p,1,s) == +/-2 (mod n)
                  or
                lucasv(p,1,s*(2**t)) == 0 (mod n) for some t, 0 <= t < r

       is_fermat_prp(...)
              is_fermat_prp(n,a) will return True if n is a Fermat probable prime to the base a.
              Assuming:
                gcd(n,a) == 1

              Then a Fermat probable prime requires:
                a**(n-1) == 1 (mod n)

       is_fibonacci_prp(...)
              is_fibonacci_prp(n,p,q)  will  return  True if n is a Fibonacci probable prime with
              parameters (p,q).
              Assuming:
                n is odd
                p > 0, q = +/-1
                p*p - 4*q != 0

              Then a Fibonacci probable prime requires:
                lucasv(p,q,n) == p (mod n).

       is_lucas_prp(...)
              is_lucas_prp(n,p,q) will return True if n is a Lucas probable prime with parameters
              (p,q).
              Assuming:
                n is odd
                D = p*p - 4*q, D != 0
                gcd(n, 2*q*D) == 1

              Then a Lucas probable prime requires:
                lucasu(p,q,n - Jacobi(D,n)) == 0 (mod n)

       is_selfridge_prp(...)
              is_selfridge_prp(n)  will  return True if n is a Lucas probable prime with Selfidge
              parameters (p,q). The Selfridge parameters are chosen by finding the first  element
              D in the sequence {5, -7, 9, -11, 13, ...} such that Jacobi(D,n) == -1. Let p=1 and
              q = (1-D)/4 and then perform a Lucas probable prime test.

       is_strong_bpsw_prp(...)
              is_strong_bpsw_prp(n)    will    return    True    if     n     is     a     strong
              Baillie-Pomerance-Selfridge-Wagstaff  probable  prime. A strong BPSW probable prime
              passes the is_strong_prp() test with base 2 and the is_strongselfridge_prp() test.

       is_strong_lucas_prp(...)
              is_strong_lucas_prp(n,p,q) will return True if n is a strong Lucas  probable  prime
              with parameters (p,q).
              Assuming:
                n is odd
                D = p*p - 4*q, D != 0
                gcd(n, 2*q*D) == 1
                n = s*(2**r) + Jacobi(D,n), s odd

              Then a strong Lucas probable prime requires:
                lucasu(p,q,s) == 0 (mod n)
                  or
                lucasv(p,q,s*(2**t)) == 0 (mod n) for some t, 0 <= t < r

       is_strong_prp(...)
              is_strong_prp(n,a)  will  return True if n is a strong (also known as Miller-Rabin)
              probable prime to the base a.
              Assuming:
                gcd(n,a) == 1
                n is odd
                n = s*(2**r) + 1, with s odd

              Then a strong probable prime requires one of the following is true:
                a**s == 1 (mod n)
                  or
                a**(s*(2**t)) == -1 (mod n) for some t, 0 <= t < r.

       is_strong_selfridge_prp(...)
              is_strong_selfridge_prp(n) will return True if n is a strong Lucas  probable  prime
              with  Selfidge parameters (p,q). The Selfridge parameters are chosen by finding the
              first element D in the sequence {5, -7, 9, -11, 13, ...} such that  Jacobi(D,n)  ==
              -1. Let p=1 and q = (1-D)/4 and then perform a strong Lucas probable prime test.

       lucasu(...)
              lucasu(p,q,k)  will return the k-th element of the Lucas U sequence defined by p,q.
              p*p - 4*q must not equal 0; k must be greater than or equal to 0.

       lucasu_mod(...)
              lucasu_mod(p,q,k,n) will return the k-th element of the Lucas U sequence defined by
              p,q  (mod  n).  p*p - 4*q must not equal 0; k must be greater than or equal to 0; n
              must be greater than 0.

       lucasv(...)
              lucasv(p,q,k) will return the k-th element of  the  Lucas  V  sequence  defined  by
              parameters (p,q). p*p - 4*q must not equal 0; k must be greater than or equal to 0.

       lucasv_mod(...)
              lucasv_mod(p,q,k,n) will return the k-th element of the Lucas V sequence defined by
              parameters (p,q) (mod n). p*p - 4*q must not equal 0; k must  be  greater  than  or
              equal to 0; n must be greater than 0.

MULTIPLE-PRECISION RATIONALS

       gmpy2  provides  a  rational  type  call  mpq.  It  should  be  a replacement for Python's
       fractions.Fraction module.

          >>> import gmpy2
          >>> from gmpy2 import mpq
          >>> mpq(1,7)
          mpq(1,7)
          >>> mpq(1,7) * 11
          mpq(11,7)
          >>> mpq(11,7)/13
          mpq(11,91)

   mpq Methods
       digits(...)
              x.digits([base=10]) returns a Python string representing x in the given base (2  to
              62,  default  is  10).  A  leading  '-'  is present if x < 0, but no leading '+' is
              present if x >= 0.

   mpq Attributes
       denominator
              x.denominator returns the denominator of x.

       numerator
              x.numerator returns the numerator of x.

   mpq Functions
       add(...)
              add(x, y) returns x + y. The result type depends on the input types.

       div(...)
              div(x, y) returns x / y. The result type depends on the input types.

       f2q(...)
              f2q(x[, err]) returns the best mpq approximating x to within  relative  error  err.
              Default  is  the  precision  of x. If x is not an mpfr, it is converted to an mpfr.
              Uses Stern-Brocot tree to find the best approximation. An mpz is  returned  if  the
              denominator is 1. If err < 0, then the relative error sought is 2.0 ** err.

       mpq(...)
              mpq() returns an mpq object set to 0/1.

              mpq(n)  returns  an  mpq object with a numeric value n. Decimal and Fraction values
              are converted exactly.

              mpq(n, m) returns an mpq object with a numeric value n / m.

              mpq(s[, base=10]) returns an mpq object from a string s made up of  digits  in  the
              given  base.  s  may  be made up of two numbers in the same base separated by a '/'
              character. If base == 10, then an embedded '.' indicates a number  with  a  decimal
              fractional part.

       mul(...)
              mul(x, y) returns x * y. The result type depends on the input types.

       qdiv(...)
              qdiv(x[,  y=1])  returns  x/y  as  mpz  if  possible, or as mpq if x is not exactly
              divisible by y.

       sub(...)
              sub(x, y) returns x - y. The result type depends on the input types.

MULTIPLE-PRECISION REALS

       gmpy2 replaces the mpf type from gmpy 1.x with a new mpfr type based on the MPFR  library.
       The  new  mpfr  type  supports  correct  rounding,  selectable  rounding  modes,  and many
       trigonometric, exponential, and special functions. A context manager is  used  to  control
       precision, rounding modes, and the behavior of exceptions.

       The  default  precision of an mpfr is 53 bits - the same precision as Python's float type.
       If the precision is changed, then mpfr(float('1.2')) differs  from  mpfr('1.2').  To  take
       advantage  of  the  higher  precision  provided by the mpfr type, always pass constants as
       strings.

          >>> import gmpy2
          >>> from gmpy2 import mpfr
          >>> mpfr('1.2')
          mpfr('1.2')
          >>> mpfr(float('1.2'))
          mpfr('1.2')
          >>> gmpy2.get_context().precision=100
          >>> mpfr('1.2')
          mpfr('1.2000000000000000000000000000006',100)
          >>> mpfr(float('1.2'))
          mpfr('1.1999999999999999555910790149937',100)
          >>>

   Contexts
       WARNING:
          Contexts and context managers are not thread-safe! Modifying the context in one  thread
          will impact all other threads.

       A  context  is  used  to  control the behavior of mpfr and mpc arithmetic.  In addition to
       controlling the precision, the  rounding  mode  can  be  specified,  minimum  and  maximum
       exponent  values  can  be  changed,  various  exceptions can be raised or ignored, gradual
       underflow can be enabled, and returning complex results can be enabled.

       gmpy2.context()   creates   a   new   context   with   all   options   set   to   default.
       gmpy2.set_context(ctx)  will  set  the  active  context  to ctx.  gmpy2.get_context() will
       return a reference to the active context. Note that contexts are  mutable:  modifying  the
       reference  returned by get_context() will modify the active context until a new context is
       enabled with set_context(). The copy() method of a context  will  return  a  copy  of  the
       context.

       The following example just modifies the precision. The remaining options will be discussed
       later.

          >>> gmpy2.set_context(gmpy2.context())
          >>> gmpy2.get_context()
          context(precision=53, real_prec=Default, imag_prec=Default,
                  round=RoundToNearest, real_round=Default, imag_round=Default,
                  emax=1073741823, emin=-1073741823,
                  subnormalize=False,
                  trap_underflow=False, underflow=False,
                  trap_overflow=False, overflow=False,
                  trap_inexact=False, inexact=False,
                  trap_invalid=False, invalid=False,
                  trap_erange=False, erange=False,
                  trap_divzero=False, divzero=False,
                  trap_expbound=False,
                  allow_complex=False)
          >>> gmpy2.sqrt(5)
          mpfr('2.2360679774997898')
          >>> gmpy2.get_context().precision=100
          >>> gmpy2.sqrt(5)
          mpfr('2.2360679774997896964091736687316',100)
          >>> gmpy2.get_context().precision+=20
          >>> gmpy2.sqrt(5)
          mpfr('2.2360679774997896964091736687312762351',120)
          >>> ctx=gmpy2.get_context()
          >>> ctx.precision+=20
          >>> gmpy2.sqrt(5)
          mpfr('2.2360679774997896964091736687312762354406182',140)
          >>> gmpy2.set_context(gmpy2.context())
          >>> gmpy2.sqrt(5)
          mpfr('2.2360679774997898')
          >>> ctx.precision+=20
          >>> gmpy2.sqrt(5)
          mpfr('2.2360679774997898')
          >>> gmpy2.set_context(ctx)
          >>> gmpy2.sqrt(5)
          mpfr('2.2360679774997896964091736687312762354406183596116',160)
          >>>

   Context Attributes
       precision
              This attribute controls the precision of an mpfr result. The precision is specified
              in  bits,  not  decimal  digits.  The  maximum  precision  that can be specified is
              platform dependent and can be retrieved with get_max_precision().

       NOTE:
          Specifying a value for precision that is too close to the maximum precision will  cause
          the MPFR library to fail.

       real_prec
              This  attribute  controls  the precision of the real part of an mpc result.  If the
              value is Default, then the value of the precision attribute is used.

       imag_prec
              This attribute controls the precision of the imaginary part of an  mpc  result.  If
              the value is Default, then the value of real_prec is used.

       round  There are five rounding modes available to mpfr types:

              RoundAwayZero
                     The result is rounded away from 0.0.

              RoundDown
                     The result is rounded towards -Infinity.

              RoundToNearest
                     Round to the nearest value; ties are rounded to an even value.

              RoundToZero
                     The result is rounded towards 0.0.

              RoundUp
                     The result is rounded towards +Infinity.

       real_round
              This  attribute  controls  the rounding mode for the real part of an mpc result. If
              the value is Default, then  the  value  of  the  round  attribute  is  used.  Note:
              RoundAwayZero is not a valid rounding mode for mpc.

       imag_round
              This  attribute controls the rounding mode for the imaginary part of an mpc result.
              If the value is Default, then the value of the real_round attribute is used.  Note:
              RoundAwayZero is not a valid rounding mode for mpc.

       emax   This  attribute  controls  the  maximum  allowed  exponent  of an mpfr result.  The
              maximum exponent is platform dependent and can be retrieved with get_emax_max().

       emin   This attribute controls the minimum  allowed  exponent  of  an  mpfr  result.   The
              minimum exponent is platform dependent and can be retrieved with get_emin_min().

       NOTE:
          It  is possible to change the values of emin/emax such that previous mpfr values are no
          longer valid numbers but should either underflow to +/-0.0 or overflow to  +/-Infinity.
          To raise an exception if this occurs, see trap_expbound.

       subnormalize
              The  usual  IEEE-754  floating point representation supports gradual underflow when
              the minimum exponent is reached. The MFPR library does not enable gradual underflow
              by  default  but  it  can  be  enabled  to  precisely mimic the results of IEEE-754
              floating point operations.

       trap_underflow
              If set to False, a result that is smaller than the smallest possible mpfr given the
              current   exponent   range  will  be  replaced  by  +/-0.0.  If  set  to  True,  an
              UnderflowResultError exception is raised.

       underflow
              This flag is not user controllable. It is automatically set if a result underflowed
              to +/-0.0 and trap_underflow is False.

       trap_overflow
              If  set  to False, a result that is larger than the largest possible mpfr given the
              current exponent range will  be  replaced  by  +/-Infinity.  If  set  to  True,  an
              OverflowResultError exception is raised.

       overflow
              This  flag is not user controllable. It is automatically set if a result overflowed
              to +/-Infinity and trap_overflow is False.

       trap_inexact
              This attribute controls whether or not an InexactResultError exception is raised if
              an  inexact  result is returned. To check if the result is greater or less than the
              exact result, check the rc attribute of the mpfr result.

       inexact
              This flag is not user controllable. It is automatically set if an inexact result is
              returned.

       trap_invalid
              This attribute controls whether or not an InvalidOperationError exception is raised
              if a numerical result is not defined. A special NaN (Not-A-Number)  value  will  be
              returned  if  an exception is not raised.  The InvalidOperationError is a sub-class
              of Python's ValueError.

              For  example,  gmpy2.sqrt(-2)  will  normally  return  mpfr('nan').   However,   if
              allow_complex is set to True, then an mpc result will be returned.

       invalid
              This  flag  is  not  user  controllable.  It  is  automatically  set  if an invalid
              (Not-A-Number) result is returned.

       trap_erange
              This attribute controls whether or  not  a  RangeError  exception  is  raised  when
              certain   operations   are  performed  on  NaN  and/or  Infinity  values.   Setting
              trap_erange to True can be used to raise an exception if comparisons are  attempted
              with a NaN.

                 >>> gmpy2.set_context(gmpy2.context())
                 >>> mpfr('nan') == mpfr('nan')
                 False
                 >>> gmpy2.get_context().trap_erange=True
                 >>> mpfr('nan') == mpfr('nan')
                 Traceback (most recent call last):
                   File "<stdin>", line 1, in <module>
                 gmpy2.RangeError: comparison with NaN
                 >>>

       erange This  flag  is  not  user  controllable. It is automatically set if an erange error
              occurred.

       trap_divzero
              This attribute controls whether or not a DivisionByZeroError exception is raised if
              division   by  0  occurs.  The  DivisionByZeroError  is  a  sub-class  of  Python's
              ZeroDivisionError.

       divzero
              This flag is not user controllable. It is automatically set if a division  by  zero
              occurred and NaN result was returned.

       trap_expbound
              This  attribute  controls  whether  or not an ExponentOutOfBoundsError exception is
              raised if exponents in an operand are outside the current emin/emax limits.

       allow_complex
              This attribute controls whether or not an mpc result can be  returned  if  an  mpfr
              result would normally not be possible.

   Context Methods
       clear_flags()
              Clear the underflow, overflow, inexact, invalid, erange, and divzero flags.

       copy() Return a copy of the context.

   Contexts and the with statement
       Contexts  can  also be used in conjunction with Python's with ... statement to temporarily
       change the context settings for a block of code and then  restore  the  original  settings
       when the block of code exits.

       gmpy2.local_context()  first save the current context and then creates a new context based
       on a context passed as the first argument, or the current context if no context is passed.
       The  new  context  is  modified  if any optional keyword arguments are given. The original
       active context is restored when the block completes.

       In the following example, the current context is saved by gmpy2.local_context()  and  then
       the block begins with a copy of the default context and the precision set to 100. When the
       block is finished, the original context is restored.

          >>> with gmpy2.local_context(gmpy2.context(), precision=100) as ctx:
          ...   print(gmpy2.sqrt(2))
          ...   ctx.precision += 100
          ...   print(gmpy2.sqrt(2))
          ...
          1.4142135623730950488016887242092
          1.4142135623730950488016887242096980785696718753769480731766796
          >>>

       A context object can also be used directly to create a context  manager  block.   However,
       instead  of  restoring  the  context  to the active context when the with ... statement is
       executed,  the  restored  context  is  the  context  used  before  any  keyword   argument
       modifications.

       The code:

       ::     with gmpy2.ieee(64) as ctx:

       is equivalent to:

       ::     gmpy2.set_context(gmpy2.ieee(64)) with gmpy2.local_context() as ctx:

       Contexts  that  implement  the  standard  single, double, and quadruple precision floating
       point types can be created using ieee().

   mpfr Methods
       as_integer_ratio()
              Returns a 2-tuple containing the numerator and  denominator  after  converting  the
              mpfr object into the exact rational equivalent. The return 2-tuple is equivalent to
              Python's as_integer_ratio() method of built-in float objects.

       as_mantissa_exp()
              Returns a 2-tuple containing the mantissa and exponent.

       as_simple_fraction()
              Returns an mpq containing the simplest rational value that  approximates  the  mpfr
              value with an error less than 1/(2**precision).

       conjugate()
              Returns  the  complex  conjugate.  For mpfr objects, returns a copy of the original
              object.

       digits()
              Returns a 3-tuple containing the mantissa, the exponent, and the number of bits  of
              precision. The mantissa is represented as a string in the specified base with up to
              'prec' digits. If 'prec' is 0, as many digits that are available are  returned.  No
              more digits than available given x's precision are returned. 'base' must be between
              2 and 62, inclusive.

       is_integer()
              Returns True if the mpfr object is an integer.

   mpfr Attributes
       imag   Returns the imaginary component. For mpfr objects, returns 0.

       precision
              Returns the precision of the mpfr object.

       rc     The result code (also known as ternary value in the MPFR documentation) is 0 if the
              value  of  the mpfr object is exactly equal to the exact, infinite precision value.
              If the result code is 1, then the value of the mpfr  object  is  greater  than  the
              exact  value.  If  the result code is -1, then the value of the mpfr object is less
              than the exact, infinite precision value.

       real   Returns the real component. For mpfr  objects,  returns  a  copy  of  the  original
              object.

   mpfr Functions
       acos(...)
              acos(x)   returns   the   arc-cosine   of   x.   x   is  measured  in  radians.  If
              context.allow_complex is True, then an mpc result will be returned for abs(x) > 1.

       acosh(...)
              acosh(x) returns the inverse hyperbolic cosine of x.

       add(...)
              add(x, y) returns x + y. The type of the result  is  based  on  the  types  of  the
              arguments.

       agm(...)
              agm(x, y) returns the arithmetic-geometric mean of x and y.

       ai(...)
              ai(x) returns the Airy function of x.

       asin(...)
              asin(x)   returns   the   arc-sine   of   x.   x   is   measured   in  radians.  If
              context.allow_complex is True, then an mpc result will be returned for abs(x) > 1.

       asinh(...)
              asinh(x) return the inverse hyperbolic sine of x.

       atan(...)
              atan(x) returns the arc-tangent of x. x is measured in radians.

       atan2(...)
              atan2(y, x) returns the arc-tangent of (y/x).

       atanh(...)
              atanh(x) returns the inverse hyperbolic tangent of x. If  context.allow_complex  is
              True, then an mpc result will be returned for abs(x) > 1.

       cbrt(...)
              cbrt(x) returns the cube root of x.

       ceil(...)
              ceil(x) returns the 'mpfr' that is the smallest integer >= x.

       check_range(...)
              check_range(x) return a new 'mpfr' with exponent that lies within the current range
              of emin and emax.

       const_catalan(...)
              const_catalan([precision=0]) returns the Catalan's  constant  using  the  specified
              precision. If no precision is specified, the default precision is used.

       const_euler(...)
              const_euler([precision=0])   returns  the  Euler's  constant  using  the  specified
              precision. If no precision is specified, the default precision is used.

       const_log2(...)
              const_log2([precision=0]) returns the log2 constant using the specified  precision.
              If no precision is specified, the default precision is used.

       const_pi(...)
              const_pi([precision=0])  returns  the constant pi using the specified precision. If
              no precision is specified, the default precision is used.

       context(...)
              context() returns a new context manager controlling MPFR and MPC arithmetic.

       cos(...)
              cos(x) returns the cosine of x. x is measured in radians.

       cosh(...)
              cosh(x) returns the hyperbolic cosine of x.

       cot(...)
              cot(x) returns the cotangent of x. x is measured in radians.

       coth(...)
              coth(x) returns the hyperbolic cotangent of x.

       csc(...)
              csc(x) returns the cosecant of x. x is measured in radians.

       csch(...)
              csch(x) returns the hyperbolic cosecant of x.

       degrees(...)
              degrees(x) converts an angle measurement x from radians to degrees.

       digamma(...)
              digamma(x) returns the digamma of x.

       div(...)
              div(x, y) returns x / y. The type of the result  is  based  on  the  types  of  the
              arguments.

       div_2exp(...)
              div_2exp(x, n) returns an 'mpfr' or 'mpc' divided by 2**n.

       eint(...)
              eint(x) returns the exponential integral of x.

       erf(...)
              erf(x) returns the error function of x.

       erfc(...)
              erfc(x) returns the complementary error function of x.

       exp(...)
              exp(x) returns e**x.

       exp10(...)
              exp10(x) returns 10**x.

       exp2(...)
              exp2(x) returns 2**x.

       expm1(...)
              expm1(x)  returns  e**x  -  1.  expm1()  is more accurate than exp(x) - 1 when x is
              small.

       f2q(...)
              f2q(x[,err]) returns the simplest mpq approximating x to within relative error err.
              Default  is  the  precision  of  x.  Uses  Stern-Brocot  tree  to find the simplest
              approximation. An mpz is returned if the denominator is 1. If err<0,  error  sought
              is 2.0 ** err.

       factorial(...)
              factorial(n) returns the floating-point approximation to the factorial of n.

              See fac(n) to get the exact integer result.

       floor(...)
              floor(x) returns the 'mpfr' that is the smallest integer <= x.

       fma(...)
              fma(x, y, z) returns correctly rounded result of (x * y) + z.

       fmma(...)
              fmma(x,  y,  z, t) returns correctly rounded result of (x * y) + (z * t).  Requires
              MPFR 4.

       fmms(...)
              fmms(x, y, z, t) returns correctly rounded result of (x * y) - (z *  t).   Requires
              MPFR 4.

       fmod(...)
              fmod(x, y) returns x - n*y where n is the integer quotient of x/y, rounded to 0.

       fms(...)
              fms(x, y, z) returns correctly rounded result of (x * y) - z.

       frac(...)
              frac(x) returns the fractional part of x.

       frexp(...)
              frexp(x) returns a tuple containing the exponent and mantissa of x.

       fsum(...)
              fsum(iterable) returns the accurate sum of the values in the iterable.

       gamma(...)
              gamma(x) returns the gamma of x.

       get_exp(...)
              get_exp(mpfr)  returns  the  exponent of an mpfr. Returns 0 for NaN or Infinity and
              sets the erange flag and will raise an exception if trap_erange is set.

       hypot(...)
              hypot(y, x) returns square root of (x**2 + y**2).

       ieee(...)
              ieee(bitwidth) returns a context with settings for 32-bit (aka single), 64-bit (aka
              double), or 128-bit (aka quadruple) precision floating point types.

       inf(...)
              inf(n)  returns  an  mpfr initialized to Infinity with the same sign as n.  If n is
              not given, +Infinity is returned.

       is_finite(...)
              is_finite(x) returns True if x is an actual number (i.e. not NaN or Infinity).

       is_inf(...)
              is_inf(x) returns True if x is Infinity or -Infinity.

              NOTE:
                 is_inf() is deprecated; please use if_infinite().

       is_infinite(...)
              is_infinite(x) returns True if x Infinity or -Infinity.

       is_nan(...)
              is_nan(x) returns True if x is NaN (Not-A-Number).

       is_number(...)
              is_number(x) returns True if x is an actual number (i.e. not NaN or Infinity).

              NOTE:
                 is_number() is deprecated; please use is_finite().

       is_regular(...)
              is_regular(x) returns True if x is not zero, NaN, or Infinity.

       is_signed(...)
              is_signed(x) returns True if the sign bit of x is set.

       is_unordered(...)
              is_unordered(x,y) returns True if either x and/or y is NaN.

       is_zero(...)
              is_zero(x) returns True if x is zero.

       j0(...)
              j0(x) returns the Bessel function of the first kind of order 0 of x.

       j1(...)
              j1(x) returns the Bessel function of the first kind of order 1 of x.

       jn(...)
              jn(x,n) returns the Bessel function of the first kind of order n of x.

       lgamma(...)
              lgamma(x) returns a tuple  containing  the  logarithm  of  the  absolute  value  of
              gamma(x) and the sign of gamma(x)

       li2(...)
              li2(x) returns the real part of dilogarithm of x.

       lngamma(...)
              lngamma(x) returns the logarithm of gamma(x).

       log(...)
              log(x) returns the natural logarithm of x.

       log10(...)
              log10(x) returns the base-10 logarithm of x.

       log1p(...)
              log1p(x) returns the natural logarithm of (1+x).

       log2(...)
              log2(x) returns the base-2 logarithm of x.

       max2(...)
              max2(x,  y)  returns the maximum of x and y. The result may be rounded to match the
              current context. Use the builtin max() to get an exact copy of the  largest  object
              without any rounding.

       min2(...)
              min2(x,  y)  returns the minimum of x and y. The result may be rounded to match the
              current context. Use the builtin min() to get an exact copy of the smallest  object
              without any rounding.

       modf(...)
              modf(x) returns a tuple containing the integer and fractional portions of x.

       mpfr(...)
              mpfr() returns and mpfr object set to 0.0.

              mpfr(n[,  precision=0])  returns an mpfr object after converting a numeric value n.
              If no precision, or a precision of 0, is specified; the precision is taken from the
              current context.

              mpfr(s[,  precision=0[, [base=0]]) returns an mpfr object after converting a string
              's' made up of digits in the given base, possibly with fractional part (with period
              as  a separator) and/or exponent (with exponent marker 'e' for base<=10, else '@').
              If no precision, or a precision of 0, is specified; the precision is taken from the
              current context. The base of the string representation must be 0 or in the interval
              2 ... 62. If the base is 0, the leading digits of the string are used  to  identify
              the base: 0b implies base=2, 0x implies base=16, otherwise base=10 is assumed.

       mpfr_from_old_binary(...)
              mpfr_from_old_binary(string)  returns  an  mpfr  from a GMPY 1.x binary mpf format.
              Please use to_binary()/from_binary() to convert GMPY2 objects to or from  a  binary
              format.

       mpfr_grandom(...)
              mpfr_grandom(random_state)  returns  two random numbers with Gaussian distribution.
              The parameter random_state must be created by random_state() first.

       mpfr_random(...)
              mpfr_random(random_state) returns a uniformly distributed number between [0,1]. The
              parameter random_state must be created by random_state() first.

       mul(...)
              mul(x,  y)  returns  x  *  y.  The  type of the result is based on the types of the
              arguments.

       mul_2exp(...)
              mul_2exp(x, n) returns 'mpfr' or 'mpc' multiplied by 2**n.

       nan(...)
              nan() returns an 'mpfr' initialized to NaN (Not-A-Number).

       next_above(...)
              next_above(x) returns the next 'mpfr' from x toward +Infinity.

       next_below(...)
              next_below(x) returns the next 'mpfr' from x toward -Infinity.

       radians(...)
              radians(x) converts an angle measurement x from degrees to radians.

       rec_sqrt(...)
              rec_sqrt(x) returns the reciprocal of the square root of x.

       reldiff(...)
              reldiff(x, y) returns the relative difference between x and y. Result is  equal  to
              abs(x-y)/x.

       remainder(...)
              remainder(x,  y) returns x - n*y where n is the integer quotient of x/y, rounded to
              the nearest integer and ties rounded to even.

       remquo(...)
              remquo(x, y) returns a tuple containing the remainder(x,y) and the low bits of  the
              quotient.

       rint(...)
              rint(x) returns x rounded to the nearest integer using the current rounding mode.

       rint_ceil(...)
              rint_ceil(x) returns x rounded to the nearest integer by first rounding to the next
              higher or equal integer and then, if needed, using the current rounding mode.

       rint_floor(...)
              rint_floor(x) returns x rounded to the nearest integer by  first  rounding  to  the
              next lower or equal integer and then, if needed, using the current rounding mode.

       rint_round(...)
              rint_round(x)  returns  x  rounded  to the nearest integer by first rounding to the
              nearest integer (ties away from 0) and then, if needed, using the current  rounding
              mode.

       rint_trunc(...)
              rint_trunc(x)  returns  x  rounded to the nearest integer by first rounding towards
              zero and then, if needed, using the current rounding mode.

       root(...)
              root(x, n) returns n-th root of x. The result always an mpfr.

       round2(...)
              round2(x[, n]) returns x rounded to n bits. Uses default  precision  if  n  is  not
              specified.  See  round_away()  to access the mpfr_round() function. Use the builtin
              round() to round x to n decimal digits.

       round_away(...)
              round_away(x) returns an mpfr by rounding x the nearest integer, with ties  rounded
              away from 0.

       sec(...)
              sec(x) returns the secant of x. x is measured in radians.

       sech(...)
              sech(x) returns the hyperbolic secant of x.

       set_exp(...)
              set_exp(x,  n) sets the exponent of a given mpfr to n. If n is outside the range of
              valid exponents, set_exp() will set the erange flag and either return the  original
              value or raise an exception if trap_erange is set.

       set_sign(...)
              set_sign(x,  bool)  returns a copy of x with it's sign bit set if bool evaluates to
              True.

       sign(...)
              sign(x) returns -1 if x < 0, 0 if x == 0, or +1 if x >0.

       sin(...)
              sin(x) returns the sine of x. x is measured in radians.

       sin_cos(...)
              sin_cos(x) returns a tuple containing the sine and cosine of x. x  is  measured  in
              radians.

       sinh(...)
              sinh(x) returns the hyberbolic sine of x.

       sinh_cosh(...)
              sinh_cosh(x) returns a tuple containing the hyperbolic sine and cosine of x.

       sqrt(...)
              sqrt(x)  returns  the square root of x. If x is integer, rational, or real, then an
              mpfr will be returned.  If  x  is  complex,  then  an  mpc  will  be  returned.  If
              context.allow_complex is True, negative values of x will return an mpc.

       square(...)
              square(x)  returns  x  *  x.  The  type  of the result is based on the types of the
              arguments.

       sub(...)
              sub(x, y) returns x - y. The type of the result  is  based  on  the  types  of  the
              arguments.

       tan(...)
              tan(x) returns the tangent of x. x is measured in radians.

       tanh(...)
              tanh(x) returns the hyperbolic tangent of x.

       trunc(...)
              trunc(x) returns an 'mpfr' that is x truncated towards 0. Same as x.floor() if x>=0
              or x.ceil() if x<0.

       y0(...)
              y0(x) returns the Bessel function of the second kind of order 0 of x.

       y1(...)
              y1(x) returns the Bessel function of the second kind of order 1 of x.

       yn(...)
              yn(x,n) returns the Bessel function of the second kind of order n of x.

       zero(...)
              zero(n) returns an mpfr initialized to 0.0 with the same sign as n.  If  n  is  not
              given, +0.0 is returned.

       zeta(...)
              zeta(x) returns the Riemann zeta of x.

   mpfr Formatting
       The mpfr type supports the __format__() special method to allow custom output formatting.

       __format__(...)
              x.__format__(fmt) returns a Python string by formatting 'x' using the format string
              'fmt'. A valid format string consists of:
              optional alignment code:
                '<' -> left shifted in field
                '>' -> right shifted in field
                '^' -> centered in field
              optional leading sign code
                '+' -> always display leading sign
                '-' -> only display minus for negative values
                ' ' -> minus for negative values, space for positive values
              optional width.precision
              optional rounding mode:
                'U' -> round toward plus infinity
                'D' -> round toward minus infinity
                'Y' -> round away from zero
                'Z' -> round toward zero
                'N' -> round to nearest
              optional conversion code:
                'a','A' -> hex format
                'b'     -> binary format
                'e','E' -> scientific format
                'f','F' -> fixed point format
                'g','G' -> fixed or scientific format

              NOTE:
                 The formatting codes must be specified in the order shown above.

          >>> import gmpy2
          >>> from gmpy2 import mpfr
          >>> a=mpfr("1.23456")
          >>> "{0:15.3f}".format(a)
          '          1.235'
          >>> "{0:15.3Uf}".format(a)
          '          1.235'
          >>> "{0:15.3Df}".format(a)
          '          1.234'
          >>> "{0:.3Df}".format(a)
          '1.234'
          >>> "{0:+.3Df}".format(a)
          '+1.234'

MULTIPLE-PRECISION COMPLEX

       gmpy2 adds a multiple-precision complex type called mpc that is based on the MPC  library.
       The context manager settings for mpfr arithmetic are applied to mpc arithmetic by default.
       It is possible to specify different precision and rounding modes for  both  the  real  and
       imaginary components of an mpc.

          >>> import gmpy2
          >>> from gmpy2 import mpc
          >>> gmpy2.sqrt(mpc("1+2j"))
          mpc('1.272019649514069+0.78615137775742328j')
          >>> gmpy2.get_context(real_prec=100,imag_prec=200)
          context(precision=53, real_prec=100, imag_prec=200,
                  round=RoundToNearest, real_round=Default, imag_round=Default,
                  emax=1073741823, emin=-1073741823,
                  subnormalize=False,
                  trap_underflow=False, underflow=False,
                  trap_overflow=False, overflow=False,
                  trap_inexact=False, inexact=True,
                  trap_invalid=False, invalid=False,
                  trap_erange=False, erange=False,
                  trap_divzero=False, divzero=False,
                  trap_expbound=False,
                  allow_complex=False)
          >>> gmpy2.sqrt(mpc("1+2j"))
          mpc('1.2720196495140689642524224617376+0.78615137775742328606955858584295892952312205783772323766490213j',(100,200))

       Exceptions  are  normally  raised  in  Python  when  the result of a real operation is not
       defined over the reals; for example, sqrt(-4) will raise an exception. The default context
       in  gmpy2  implements  the  same  behavior  but  by setting allow_complex to True, complex
       results will be returned.

          >>> import gmpy2
          >>> from gmpy2 import mpc
          >>> gmpy2.sqrt(-4)
          mpfr('nan')
          >>> gmpy2.get_context(allow_complex=True)
          context(precision=53, real_prec=Default, imag_prec=Default,
                  round=RoundToNearest, real_round=Default, imag_round=Default,
                  emax=1073741823, emin=-1073741823,
                  subnormalize=False,
                  trap_underflow=False, underflow=False,
                  trap_overflow=False, overflow=False,
                  trap_inexact=False, inexact=False,
                  trap_invalid=False, invalid=True,
                  trap_erange=False, erange=False,
                  trap_divzero=False, divzero=False,
                  trap_expbound=False,
                  allow_complex=True)
          >>> gmpy2.sqrt(-4)
          mpc('0.0+2.0j')

   mpc Methods
       conjugate()
              Returns the complex conjugate.

       digits()
              Returns a two element tuple where each element represents the  real  and  imaginary
              components  as  a  3-tuple containing the mantissa, the exponent, and the number of
              bits of precision. The mantissa is represented as a string in  the  specified  base
              with  up  to  'prec'  digits. If 'prec' is 0, as many digits that are available are
              returned. No more digits than available given x's precision  are  returned.  'base'
              must be between 2 and 62, inclusive.

   mpc Attributes
       imag   Returns the imaginary component.

       precision
              Returns a 2-tuple containing the precision of the real and imaginary components.

       rc     Returns  a  2-tuple  containing  the  ternary  value  of  the  real  and  imaginary
              components. The ternary value is 0 if the value of the component is  exactly  equal
              to  the exact, infinite precision value. If the result code is 1, then the value of
              the component is greater than the exact value. If the result code is -1,  then  the
              value of the component is less than the exact, infinite precision value.

       real   Returns the real component.

   mpc Functions
       acos(...)
              acos(x) returns the arc-cosine of x.

       acosh(...)
              acosh(x) returns the inverse hyperbolic cosine of x.

       add(...)
              add(x,  y)  returns  x  +  y.  The  type of the result is based on the types of the
              arguments.

       asin(...)
              asin(x) returns the arc-sine of x.

       asinh(...)
              asinh(x) return the inverse hyperbolic sine of x.

       atan(...)
              atan(x) returns the arc-tangent of x.

       atanh(...)
              atanh(x) returns the inverse hyperbolic tangent of x.

       cos(...)
              cos(x) returns the cosine of x.

       cosh(...)
              cosh(x) returns the hyperbolic cosine of x.

       div(...)
              div(x, y) returns x / y. The type of the result  is  based  on  the  types  of  the
              arguments.

       div_2exp(...)
              div_2exp(x, n) returns an 'mpfr' or 'mpc' divided by 2**n.

       exp(...)
              exp(x) returns e**x.

       fma(...)
              fma(x, y, z) returns correctly rounded result of (x * y) + z.

       fms(...)
              fms(x, y, z) returns correctly rounded result of (x * y) - z.

       is_inf(...)
              is_inf(x)  returns  True if either the real or imaginary component of x is Infinity
              or -Infinity.

       is_nan(...)
              is_nan(x) returns True if either the real  or  imaginary  component  of  x  is  NaN
              (Not-A-Number).

       is_zero(...)
              is_zero(x) returns True if x is zero.

       log(...)
              log(x) returns the natural logarithm of x.

       log10(...)
              log10(x) returns the base-10 logarithm of x.

       mpc(...)
              mpc() returns an mpc object set to 0.0+0.0j.

              mpc(c[,  precision=0])  returns  a new 'mpc' object from an existing complex number
              (either a Python complex object or another 'mpc' object). If the precision  is  not
              specified,  then the precision is taken from the current context. The rounding mode
              is always taken from the current context.

              mpc(r[,  i=0[,  precision=0]])  returns  a  new  'mpc'  object  by  converting  two
              non-complex  numbers  into the real and imaginary components of an 'mpc' object. If
              the precision is not specified, then  the  precision  is  taken  from  the  current
              context. The rounding mode is always taken from the current context.

              mpc(s[, [precision=0[, base=10]]) returns a new 'mpc' object by converting a string
              s into a complex number. If base is  omitted,  then  a  base-10  representation  is
              assumed otherwise a base between 2 and 36 can be specified. If the precision is not
              specified, then the precision is taken from the current context. The rounding  mode
              is always taken from the current context.

              In  addition  to  the  standard  Python  string representation of a complex number:
              "1+2j", the string representation  used  by  the  MPC  library:  "(1  2)"  is  also
              supported.

              NOTE:
                 The  precision can be specified either a single number that is used for both the
                 real and imaginary components, or  as  a  2-tuple  that  can  specify  different
                 precisions for the real and imaginary components.

       mpc_random(...)
              mpfc_random(random_state) returns a uniformly distributed number in the unit square
              [0,1]x[0,1]. The parameter random_state must be created by random_state() first.

       mul(...)
              mul(x, y) returns x * y. The type of the result  is  based  on  the  types  of  the
              arguments.

       mul_2exp(...)
              mul_2exp(x, n) returns 'mpfr' or 'mpc' multiplied by 2**n.

       norm(...)
              norm(x)  returns  the  norm  of  a complex x. The norm(x) is defined as x.real**2 +
              x.imag**2. abs(x) is the square root of norm(x).

       phase(...)
              phase(x) returns the phase angle, also known as argument, of a complex x.

       polar(...)
              polar(x) returns the polar coordinate form of a complex x that  is  in  rectangular
              form.

       proj(...)
              proj(x) returns the projection of a complex x on to the Riemann sphere.

       rect(...)
              rect(x)  returns  the  polar  coordinate form of a complex x that is in rectangular
              form.

       root_of_unity(...)
              root_of_unity(n, k) returns the n-th root of  mpc(1)  raised  to  the  k-th  power.
              Requires MPC 1.1.0 or greater.

       sin(...)
              sin(x) returns the sine of x.

       sinh(...)
              sinh(x) returns the hyberbolic sine of x.

       sqrt(...)
              sqrt(x)  returns  the square root of x. If x is integer, rational, or real, then an
              mpfr will be returned.  If  x  is  complex,  then  an  mpc  will  be  returned.  If
              context.allow_complex is True, negative values of x will return an mpc.

       square(...)
              square(x)  returns  x  *  x.  The  type  of the result is based on the types of the
              arguments.

       sub(...)
              sub(x, y) returns x - y. The type of the result  is  based  on  the  types  of  the
              arguments.

       tan(...)
              tan(x) returns the tangent of x. x is measured in radians.

       tanh(...)
              tanh(x) returns the hyperbolic tangent of x.

   mpc Formatting
       The mpc type supports the __format__() special method to allow custom output formatting.

       __format__(...)
              x.__format__(fmt) returns a Python string by formatting 'x' using the format string
              'fmt'. A valid format string consists of:
              optional alignment code:
                '<' -> left shifted in field
                '>' -> right shifted in field
                '^' -> centered in field
              optional leading sign code
                '+' -> always display leading sign
                '-' -> only display minus for negative values
                ' ' -> minus for negative values, space for positive values
              optional width.real_precision.imag_precision
              optional rounding mode:
                'U' -> round toward plus infinity
                'D' -> round toward minus infinity
                'Z' -> round toward zero
                'N' -> round to nearest
              optional output style:
                'P' -> Python style, 1+2j, (default)
                'M' -> MPC style, (1 2)
              optional conversion code:
                'a','A' -> hex format
                'b'     -> binary format
                'e','E' -> scientific format
                'f','F' -> fixed point format
                'g','G' -> fixed or scientific format

              NOTE:
                 The formatting codes must be specified in the order shown above.

          >>> import gmpy2
          >>> from gmpy2 import mpc
          >>> a=gmpy2.sqrt(mpc("1+2j"))
          >>> a
          mpc('1.272019649514069+0.78615137775742328j')
          >>> "{0:.4.4Mf}".format(a)
          '(1.2720 0.7862)'
          >>> "{0:.4.4f}".format(a)
          '1.2720+0.7862j'
          >>> "{0:^20.4.4U}".format(a)
          '   1.2721+0.7862j   '
          >>> "{0:^20.4.4D}".format(a)
          '   1.2720+0.7861j   '

CYTHON USAGE

       The gmpy2 module provides a C-API that can be conveniently used from  Cython.   All  types
       and functions are declared in the header gmpy2.pxd that is installed automatically in your
       Python path together with the library.

   Initialization
       In  order  to  use  the  C-API  you  need  to  make  one  call  to   the   function   void
       import_gmpy2(void).

   Types
       The  types  mpz,  mpq,  mpfr  and  mpc  are declared as extension types in gmpy2.pxd. They
       correspond respectively to  the  C  structures  MPZ_Object,  MPQ_Object,  MPFR_Object  and
       MPC_Object.

       Fast type checking can be done with the following C functions

       bint MPZ_Check(object)
              equivalent to isinstance(obj, mpz)

       bint MPQ_Check(object)
              equivalent to isinstance(obj, mpq)

       bint MPFR_Check(object)
              equivalent to isinstance(obj, mpfr)

       bint MPC_Check(object)
              equivalent to isinstance(obj, mpc)

   Object creation
       To create a new gmpy2 types there are four basic functions

       mpz GMPy_MPZ_New(void * ctx)
              create a new mpz object from a given context ctx

       mpq GMPy_MPQ_New(void * ctx)
              create a new mpq object from a given context ctx

       mpfr MPFR_New(void * ctx, mpfr_prec_t prec)
              create a new mpfr object with given context ctx and precision prec

       mpc MPC_New(void * ctx, mpfr_prec_t rprec, mpfr_prec_t iprec)
              create  a  new  mpc  object  with  given context ctx, precisions rprec and iprec of
              respectively real and imaginary parts

       The context can be set to NULL and controls the default behavior (e.g. precision).

       The gmpy2.pxd header also provides convenience macro to wrap a (copy of) a  mpz_t,  mpq_t,
       mpfr_t or a mpc_t object into the corresponding gmpy2 type.

       mpz GMPy_MPZ_From_mpz(mpz_srcptr z)
              return a new mpz object with a given mpz_t value z

       mpq GMPy_MPQ_From_mpq(mpq_srcptr q)
              return a new mpq object from a given mpq_t value q

       mpq GMPy_MPQ_From_mpz(mpz_srcptr num, mpz_srcptr den)
              return a new mpq object with a given mpz_t numerator num and mpz_t denominator den

       mpfr GMPy_MPFR_From_mpfr(mpfr_srcptr x)
              return a new mpfr object with a given mpfr_t value x

       mpc GMPy_MPC_From_mpc(mpc_srcptr c)
              return a new mpc object with a given mpc_t value c

       mpc GMPy_MPC_From_mpfr(mpfr_srcptr re, mpfr_srcptr im)
              return  a new mpc object with a given mpfr_t real part re and mpfr_t imaginary part
              im

   Access to the underlying C type
       Each of the gmpy2 objects has  a  field  corresponding  to  the  underlying  C  type.  The
       following functions give access to this field

       mpz_t MPZ(mpz)

       mpq_t MPQ(mpq)

       mpfr_t MPFR(mpfr)

       mpc_t MPC(mpc)

   Compilation
       The  header  gmpy2.pxd as well as the C header gmpy2.h from which it depends are installed
       in the Python path. In order to make Cython and the C compiler aware of the  existence  of
       these files, the Python path should be part of the include directories.

       Recall that import_gmpy2() needs to be called before any other function of the C-API.

       Here is a minimal example of a Cython file test_gmpy2.pyx

          "A minimal setup.py for compiling test_gmpy2.pyx"

          from distutils.core import setup
          from distutils.extension import Extension
          from Cython.Build import cythonize
          import sys

          ext = Extension("test_gmpy2", ["test_gmpy2.pyx"], include_dirs=sys.path, libraries=['gmp', 'mpfr', 'mpc'])

          setup(
              name="cython_gmpy_test",
              ext_modules=cythonize([ext], include_path=sys.path)
          )

       The corresponding setup.py is given below.

          "A minimal cython file test_gmpy2.pyx"

          from gmpy2 cimport *

          cdef extern from "gmp.h":
              void mpz_set_si(mpz_t, long)

          import_gmpy2()   # needed to initialize the C-API

          cdef mpz z = GMPy_MPZ_New(NULL)
          mpz_set_si(MPZ(z), -7)

          print(z + 3)

       With  these  two  files  in the same repository, you should be able to compile your module
       using

          $ python setup.py build_ext --inplace

       For more about compilation and installation of cython files and extension modules,  please
       refer to the official documentation of Cython and distutils.

CONVERSION METHODS AND GMPY2'S NUMBERS

   Conversion methods
       A python object could interact with gmpy2 if it implements one of the following methods:

       • __mpz__ : return an object of <type 'mpz'>.

       • __mpq__ : return an object of <type 'mpq'>.

       • __mpfr__ : return an object of <type 'mpfr'>.

       • __mpc__ : return an object of <type 'mpc'>.
       Implementing on of these methods allow gmpy2 to convert a python object into a gmpy2 type.
       Example::

       >>> from gmpy2 import mpz
       >>> class CustInt:
       ...     def __init__(self, x):
       ...             self.x = x
       ...     def __mpz__(self):
       ...             return mpz(self.x)
       ...
       >>> ci = CustInt(5)
       >>> z = mpz(ci); z
       mpz(5)
       >>> type(z)
       <type 'mpz'>

   Arithmetic operations
       gmpy2 allow arithmetic operations between gmpy2 numbers and objects with conversion methods.
       Operation with object that implements floating conversion and exact conversion methods are not supported.
       That means that only the following cases are supported:

       • An integer type have to implement __mpz__

       • A rational type have to implement __mpq__ and can implement __mpz__

       • A real type have to implement __mpfr__

       • A complex type have to implement __mpc__ and can implement __mpfr__

       Examples:

          >>> from gmpy2 import mpz, mpq, mpfr, mpc
          >>> class Q:
          ...     def __mpz__(self): return mpz(1)
          ...     def __mpq__(self): return mpq(3,2)
          >>> q = Q()
          >>> mpz(2) + q
          mpq(7,2)
          >>> mpq(1,2) * q
          mpq(3,4)
          >>> mpfr(10) * q
          mpfr('15.0')

CHANGES FOR GMPY2 RELEASES

   Changes in gmpy2 2.1.0b1
       • Added cmp() and cmp_abs().

       • Improved compatibility with _numbers_ protocol.

       • Many bug fixes.

   Changes in gmpy2 2.1.a05
       • Fix qdiv() not returning mpz() when it should.

       • Added root_of_unity().

   Changes in gmpy2 2.1.0a4
       • Fix issue 204; missing file for Cython.

       •

         Additional support for MPFR 4

                • Add fmma() and fmms()

   Changes in gmpy2 2.1.0a3
       • Updates to setup.py.

       •

         Initial support for MPFR4

                • Add nrandom()

                • grandom() now calls nrandom twice; may return different values versus MPFR3

                • Add rootn(); same as root() except different sign when taking even root of -0.0

   Changes in gmpy2 2.1.0a2
       • Revised build process.

       • Removal of unused code/macros.

       • Cleanup of Cython interface.

   Changes in gmpy2 2.1.0a1
       • Thread-safe  contexts  are  now  supported.  Properly  integrating  thread-safe contexts
         required an extensive rewrite of almost all internal functions.

       • MPFR and MPC are now required. It is no longer possible to build a version of gmpy2 that
         only supports the GMP library.

       • The function inverse() now raises an exception if the inverse does not exist.

       • Context methods have been added for MPFR/MPC related functions.

       • A  new  context  option  (rational_division) has been added that changes the behavior of
         integer division involving mpz instances to  return  a  rational  result  instead  of  a
         floating point result.

       • gmpy2 types are now registered in the numeric tower.

       • In  previous  versions  of gmpy2, gmpy2.mpz was a factory function that returned an  mpz
         instance. gmpy2.mpz is now an actual type. The same is true for the other gmpy2 types.

       • If a Python object has an __mpz__ method, it will  be  called  bye  mpz()  to  allow  an
         unrecognized  type  to  be  converted to an mpz instance. The same is true for the other
         gmpy2 types.

       • A new C-API and Cython interface has been added.

   Changes in gmpy2 2.0.4
       • Fix bit_scan0() for negative values.

       • Changes to setup.py to allow static linking.

       • Fix performance regression with mpmath and Python 3.

   Changes in gmpy2 2.0.3
       • Fix lucas2() and atanh(); they were returning incorrect values.

   Changes in gmpy2 2.0.2
       • Rebuild Windows binary installers due to MPIR 2.6.0 bug in next_prime().

       • Another fix for is_extra_strong_lucas_prp().

   Changes in gmpy2 2.0.1
       • Updated setup.py to work in more situations.

       • Corrected exception handling in basic operations with mpfr type.

       • Correct InvalidOperation exception not raised in certain circumstances.

       • invert() now raises an exception if the modular inverse does not exist.

       • Fixed internal exception in is_bpsw_prp() and is_strong_bpsw_prp().

       • Updated is_extra_strong_lucas_prp() to latest version.

   Changes in gmpy2 2.0.0
       • Fix  segmentation  fault  in  _mpmath_normalize   (an   undocumented   helper   function
         specifically for mpmath.)

       • Improved setup.py See below for documentation on the changes.

       • Fix issues when compiled without support for MPFR.

       • Conversion  of  too  large an mpz to float now raises OverflowError instead of returning
         inf.

       • Renamed min2()/max2() to minnum()/maxnum()

       • The build and install process (i.e. setup.py) has been completely  rewritten.   See  the
         Installation section for more information.

       • get_context() no longer accepts keyword arguments.

   Known issues in gmpy2 2.0.0
       • The test suite is still incomplete.

   Changes in gmpy2 2.0.0b4
       • Added __ceil__, __floor__, __trunc__, and __round__ methods to mpz and mpq types.

       • Added __complex__ to mpc type.

       • round(mpfr) now correctly returns an mpz type.

       • If  no arguments are given to mpz, mpq, mpfr, mpc, and xmpz, return 0 of the appropriate
         type.

       • Fix broken comparison between mpz and mpq when mpz is on the left.

       • Added __sizeof__ to all types. Note: sys.getsizeof() calls __sizeof__ to get the  memory
         size  of  a  gmpy2  object. The returned value reflects the size of the allocated memory
         which may be larger than the actual minimum memory required by the object.

   Known issues in gmpy2 2.0.0b4
       • The new test suite (test/runtest.py) is incomplete and some tests fail on Python 2.x due
         to formatting issues.

   Changes in gmpy2 2.0.0b3
       • mp_version(),  mpc_version(), and mpfr_version() now return normal strings on Python 2.x
         instead of Unicode strings.

       • Faster conversion of the standard library Fraction type to mpq.

       • Improved conversion of the Decimal type to mpfr.

       • Consistently return OverflowError when converting "inf".

       • Fix mpz.__format__() when the format code includes "#".

       • Add is_infinite() and deprecate is_inf().

       • Add is_finite() and deprecate is_number().

       • Fixed the various is_XXX() tests when used with mpc.

       • Added caching for mpc objects.

       • Faster code path for basic operation is both operands are mpfr or mpc.

       • Fix mpfr + float segmentation fault.

   Changes in gmpy2 2.0.0b2
       • Allow xmpz slice assignment to increase length of xmpz instance by  specifying  a  value
         for stop.

       • Fixed reference counting bug in several is_xxx_prp() tests.

       • Added iter_bits(), iter_clear(), iter_set() methods to xmpz.

       • Added powmod() for easy access to three argument pow().

       • Removed  addmul()  and  submul()  which were added in 2.0.0b1 since they are slower than
         just using Python code.

       • Bug fix in gcd_ext when both arguments are not mpz.

       • Added ieee() to create contexts for 32, 64, or 128 bit floats.

       • Bug fix in context() not setting emax/emin correctly if they had been changed earlier.

       • Contexts   can   be   directly   used    in    with    statement    without    requiring
         set_context()/local_context() sequence.

       • local_context() now accepts an optional context.

   Changes in gmpy2 2.0.0b1 and earlier
       • Renamed   functions   that  manipulate  individual  bits  to  bit_XXX()  to  align  with
         bit_length().

       • Added caching for mpq.

       • Added rootrem(), fib2(), lucas(), lucas2().

       • Support changed hash function in Python 3.2.

       • Added is_even(), is_odd().

       • Add caching of the calculated hash value.

       • Add xmpz (mutable mpz) type.

       • Fix mpq formatting issue.

       • Add read/write bit access using slices to xmpz.

       • Add read-only bit access using slices to mpz.

       • Add pack()/unpack() methods to split/join an integer into n-bit chunks.

       • Add support for MPFR (casevh)

       • Removed fcoform float conversion modifier.

       • Add support for MPC.

       • Added context manager.

       • Allow building with just GMP/MPIR if MPFR not available.

       • Allow building with GMP/MPIR and MPFR if MPC not available.

       • Removed most instance methods in favor of gmpy2.function. The general guideline is  that
         properties  of  an instance can be done via instance methods but functions that return a
         new result are done using gmpy2.function.

       • Added __ceil__, __floor__, and __trunc__ methods since they are called  by  math.ceil(),
         math.floor(), and math.trunc().

       • Removed gmpy2.pow() to avoid conflicts.

       • Removed gmpy2._copy and added xmpz.copy.

       • Added support for __format__.

       • Added as_integer_ratio, as_mantissa_exp, as_simple_fraction.

       • Updated rich_compare.

       • Require MPFR 3.1.0+ to get divby0 support.

       • Added fsum(), degrees(), radians().

       • Updated random number generation support.

       • Changed license to LGPL 3+.

       • Added  lucasu,  lucasu_mod,  lucasv, and lucasv_mod.  Based on code contributed by David
         Cleaver.

       • Added probable-prime tests.  Based on code contributed by David Cleaver.

       • Added to_binary()/from_binary.

       • Renamed numdigits() to num_digits().

       • Added keyword precision to constants.

       • Added addmul() and submul().

       • Added __round__(), round2(), round_away() for mpfr.

       • round() is no longer a module level function.

       • Renamed module functions min()/max() to min2()/max2().

       • No longer conflicts with builtin min() and max()

       • Removed set_debug() and related functionality.

       • genindex

       • modindex

       • search

AUTHOR

       Case Van Horsen

COPYRIGHT

       2020, 2013, 2014, 2017, 2018, 2019 Case Van Horsen