NAME

       clog, clogf, clogl - natural logarithm of a complex number

SYNOPSIS

       #include <complex.h>

       double complex clog(double complex z);
       float complex clogf(float complex z);
       long double complex clogl(long double complex z);

       Link with -lm.

DESCRIPTION

       The  logarithm  clog()  is  the  inverse  function  of  the exponential cexp(3).  Thus, if
       y = clog(z), then z = cexp(y).  The  imaginary  part  of  y  is  chosen  in  the  interval
       [-pi,pi].

       One has:

           clog(z) = log(cabs(z)) + I * carg(z)

       Note that z close to zero will cause an overflow.

VERSIONS

       These functions first appeared in glibc in version 2.1.

CONFORMING TO

       C99.

SEE ALSO

       cabs(3), cexp(3), clog10(3), clog2(3), complex(7)

COLOPHON

       This  page  is  part of release 3.54 of the Linux man-pages project.  A description of the
       project,    and    information    about    reporting    bugs,    can    be    found     at
       http://www.kernel.org/doc/man-pages/.

                                            2008-08-11                                    CLOG(3)