pmath - simple command line interface to Math::Cephes

NAME

pmath - simple command line interface to Math::Cephes

SYNOPSIS

  bash> pmath

 Interactive interface to the Math::Cephes module.
 TermReadLine enabled. Type 'help' or '?'  for help.

 pmath> setprec 4
         display set to 4 decimal places
 pmath> cos($PI)
         -1.0000
 pmath> acos(%)
          3.1416
 pmath> q
 bash>

DESCRIPTION

This script provides a simple command line interface to the Math::Cephes module. If available, it will use the Term::ReadKey and Term::ReadLine::Perl or Term::ReadLine::GNU modules to provide command line history and word completion.

Typing help or ? alone will provide a list of help topics grouped by major category name. help category will provide a listing and short description of each function within the named category. help function will provide a description and synopsis of the named function.

Entering an expression that returns a single value, such as sin($x), or one that returns multiple values, such as airy($x), will result in all return values being printed. The last (successful) single value returned is saved as the % symbol (as in Maple), so that one can do

     pmath> sin($PI/2)
            1
     pmath> asin(%)
            1.570796
     pmath>

The number of decimal places displayed can be set to j using setprec j:

     pmath> setprec 8
             display set to 8 decimal places
     pmath> $PI
             3.14159265
     pmath>

Multiple statements can be entered on a line, such as pmath> $x=1; $y=exp($x); printf(``\texp(%5.2f)=%5.2f\n'',$x,$y); exp( 1.00)= 2.72 pmath>

or on multiple lines using \ as a continuation signal:

    pmath> $x = 1; \
           $y = exp($x); \
            printf("exp(%5.2f)=%5.2f\n", $x, $y);
             exp( 1.00)= 2.72
    pmath>

To quit the program, enter q, quit, or exit.

The Math::Cephes module has some support for handling fractions and complex numbers through the Math::Cephes::Fraction and Math::Cephes::Complex modules. For fractions, one can use the fract() function to create a fraction object, and then use these in a fraction routine:

    pmath> $f=fract(1,3); $g=fract(4,3); $f->radd($g);
            5/3
    pmath> mixed(%)
            1 2/3
    pmath>

Similarly, for complex numbers one can use the cmplx() function to create a complex number object, and then use these in a complex number routine:

    pmath> $f=cmplx(1,3); $g=cmplx(4,3); $f->cadd($g);
            5+6 i
    pmath>

See the Math::Cephes::Polynomial manpage for an interface to some polynomial routines, and the Math::Cephes::Matrix manpage for some matrix routines.

BUGS

Probably. Please report any to Randy Kobes <randy@theoryx5.uwinnipeg.ca>

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