Provided by: alliance_5.0-20120515-6_amd64 bug

EXP

       exp - a multiple expession calculator.

SYNOPSIS

       exp [-vn0..4] [-o output-file] [input-file]

DESCRIPTION

       Input is an ascii format file including numeric expessions with variables.  Input file can
       includes other input files thanks to an inclusion directive.  exp reads the input files to
       write it as is in the output file, but the numeric expessions are replaced by their value.

OPTIONS

       -v     verbose mode
              0 : quiet mode
              1 : messages mess(...) are printed
              2 : few statistics
              3 : all expressions are decomposed
              4 : yacc messages

       -o output-file
              where exp writes (stdout by default).

       input-file
              where exp reads (stdin by default).

EXP FORMAT FILES

       Except the expessionsi and offline comments, the output file is identical to the flattened
       view of the input files whatever they are.  The expession forms can be either [expessions]
       or  {expessions}.   The first form is for floating point expessions, the second one is for
       integer expessions. By default, the print  format  is  respectively  %7.3f  and  %4d  (cf.
       sprintf(3)).  Offline comments begins with // and ends at the beginning of the next line.

       Examples

       •  [ 3.0 + 12.1] print 15.100

       •  { 3.0 + 12.1} print 15

       It  is  possible  to  have  more  that one expession separated by ; (semi-column). All the
       expessions of a list are computed, but only the last one is printed. If the last expession
       is empty, exp do not print anything (see Examples section).

       Examples

       •  [ 6. *2.0;
            3.0 + 12.1 ] print 15.100

       •  [ 6. *2.0;
            3.0 + 12.1; ] print nothing

       It is possible to have comments in expessions. A comment begins with # (diese) and ends to
       the carriage return.  Comment in expression is not copied to the output file.

       Example

       •  [ 3.0 + 12.1 # comment
          ] print 15.100

   Expessions
       Expession  is  a  multi-level  numeric  expession  using  numbers,  variables,  arithmetic
       operators and numeric functions.

       Examples

       •  [ i=3.0; i*12.1] print 15.100

       •  {i=3} print 3
          {i++} print 4

   Arithmetic Operators
       The operators, in order of increasing priority, are

       + -    Addition and subtraction.

       * /    Multiplication and division.

       ++ --  post-incrementation of 1, post-decrementation of 1.

       ( )    Grouping

       =      Variable affectation. The return value is the one affected.

   Boolean Operators
       > <    respectively greater than and lower than

       def(variable)
              True whenever variable is defined yet

       ndef(variable)
              True whenever variable is not defined yet

   Variables
       Expession  values  may  be  stored in simple variables.  There are three forms of variable
       name.  First, they can begin with a letter followed by any number of letters,  digits  and
       underscores;  second,  they  can begin with " (double quote) followed by any number of any
       char and ended by a "; Third they can begin with ´ (quote) then a regular expression  (see
       regex(7)) ended by ´.  exp is case sensitive.

       Examples

       •  [ VAR_1=3.0;                # first form
            "variable numero 2"=12.0; # second form
          ] print nothing

       •  [ VAR_1 * "variable numero 2" ] print 15.100

       When  a  variable appears in the right member of an affectation, exp uses its value. If it
       has never been defined, this causes a fatal error.  If it appears  the  left  member,  the
       first time it is automatically created and its value is set, or its value is changed.

   Special variables
       float_fmt,  integer_fmt  and  string_fmt  special  variables  to  redefine print format of
       floats, integers and strings. Defaults are %7.3f, %-8s and %4d. Those  variables  are  the
       only variables with a non numerical value.

       Examples

       •  [float_fmt = "%7.1f";] print nothing

       •  [ 3.0 + 12.1] print 15.1

       verbose  is  the  variable  passed  in argument list, which can be modified by the program
       itself.

       Examples  get details of expression calculation

       •  [tmp = verbose; verbose = 3; ..expressions..;
          verbose = tmp;]

   Numeric functions
       Few numeric functions are available. The form is fun(args).  The arguments take  the  form
       of  a  list  of expessions, separated with a , (comma). The number of arguments depends on
       functions.  It is possible to make a list of  arguments  with  a  regular  expession  (see
       regex(7)).  Then all matching variable names are part of the list.

       min(args) max(args)
              The minimum (resp. maximum) value of its arguments.

              Examples

              •  [min(3.0,12.1)] print 3.000

              •  [min('RW_ALU.*')] print min value of all variables begining by RW_ALU

       inf(step,val) sup(step,val)
              Two  arguments. inf (resp. sup) function rounds the second argument (val) downwards
              (resp.  upwards) to an integer number of the first argument (step).

              Examples

              •  [step=0.3;value=1.6;inf(step,value)] print 1.500

   Special functions and directives
       if(condition, expr1, expr2, ...)
              Calculates the condition if it is true (means greater  than  zero),  the  following
              expressions are all calculated.

       sort(args) rsort(args)
              sort  (resp.  reverse rsort) numerically all its arguments, each argument must be a
              variable, not directly a numeric expession. The return value is the sorted list  of
              its arguments.

       message(args)
              writes its arguments to stdout using float_fmt, one argument per line.  The form is
              : variable_name = value;, value is omitted if the variable has never been defined.
              Examples

              •  [message('"'this is a message'"');] print
                 this is a message

              •  [a1b=0; a2b=1O; a3b=5; message(a*b);] print
                 a1b      =  0.000
                 a2b      = 1O.000
                 a3b      =  5.000

              •  [string_fmt=%6s; message(sort(a*b));] print
                    a1b =  0.000
                    a3b =  5.000
                    a2b = 1O.000

       #include "filename"
              Opens the file in argument then returns to the current file as soon as the new  one
              is empty.

EXAMPLES

       Input file
              # this is a test file
              [ # few variables
                WITDH = 2;
                LENGTH = 25 ;
              ]
              this message is unchanged but all expresions are computed
                length_div_2 = [LENGTH/2]
                length_mul_2 = {LENGTH*2}
                result = [max ('leng.*')]

       Output file
              # this is a test file

              this message is unchanged but all expresions are computed
                length_div_2 =   12.500
                length_mul_2 =   50
                result =   12.500

AUTHOR

       Written by Franck Wajsburt.

SEE ALSO

       Alliance .rds file uses exp to be generated.