Yichun Zhang (章亦春) > PerlMaple > PerlMaple

Download:
PerlMaple-0.07.tar.gz

Dependencies

Annotate this POD

CPAN RT

Open  0
View/Report Bugs
Module Version: 0.07   Source  

NAME ^

PerlMaple - Perl binding for Maplesoft's Maple mathematical package

VERSION ^

This document describes PerlMaple 0.07 released on Nov 20, 2009.

SYNOPSIS ^

  use PerlMaple;

  $maple = PerlMaple->new or
      die $maple->error;
  $ans = $maple->eval_cmd('int(2*x^3,x);');
  defined $ans or die $maple->error;

  $maple->eval_cmd(<<'.');
  lc := proc( s, u, t, v )
           description "form a linear combination of the arguments";
           s * u + t * v
  end proc;
  .

  $maple = PerlMaple->new(
    PrintError => 0,
    RaiseError => 1,
  );

  print $maple->eval('solve(x^2+2*x+4, x)');  # got: -1+I*3^(1/2), -1-I*3^(1/2)
  print $maple->solve('x^2+2*x+4', 'x');  # ditto
  print $maple->eval('int(2*x^3,x)', 'x=2');  # got: 8s
  print $maple->int('2*x^3', 'x=0..2');  # ditto

  $maple->PrintError(1);
  $maple->RaiseError(0);

  print $maple->diff('2*x^3', 'x'); # got: 6*x^2
  print $maple->ifactor('1000!');  # will get a lot of stuff...

  # Advanced usage (manipulating Maple ASTs directly):
  $ast = $maple->to_ast('[1,2,3]');
  foreach ($ast->ops) {
      print;  # got 1, 2, and 3 respectively
  }

  # Get eval_cmd and other AUTOLOADed Maple function
  # to return ASTs automagically:
  $maple->ReturnAST(1);
  $ast = $maple->solve('x^2+x=0', 'x');
  if ($ast and $ast->type('exprseq')) {
    foreach ($ast->ops) {
        push @roots, $_;
    }
  }
  print "@roots";  # got: 0 -1

  $maple->ReturnAST(1);
  $res = $maple->solve('{x+y=2,x-y=3}', '{x,y}');
  if ($res->type('set')) {
      $x = first { $_->lhs eq 'x' } $res->ops;
      print $x->rhs;  # 5/2
  }

DESCRIPTION ^

Maple is a great tool for solving mathematical problems and creating interactive technical applications provided by Maplesoft. Its power of symbolic calculation is extremely impressive.

This is a simple (but already powerful) Perl binding for Maple's OpenMaple C interface. To try out this binding, you have to purchase and install the Maple software first:

http://www.maplesoft.com.

The Maple software is *not* free, sigh, unlike this CPAN distribution.

INSTALLATION ^

Currently this software is only tested on Win32 against Maple 9.01 and Maple 10.00, but it's believed to work with other versions higher than 9. If you get it work with a specific version of Maple, please send me a mail and let me know. :=)

To build this module properly, you must first have Maple 9 or better installed on your system and append the paths of maplec.h and maplec.lib in your Maple installation to the environments LIB and INC respectively. Because this module use Maple's C interface (OpenMaple) via XS.

Both maplec.h and maplec.lib (or maplec.a on *NIX systems?) are provided by your Maple installation itself. A typical path of maplec.h is "C:\Program Files\Maple 9\extern\include", which should be appended to the INCLUDE environment. And a typical path of maplec.lib is "C:\Program Files\Maple 9\bin.win", which should be appended to the LIB environment. These paths may be different on your machine but do depend on your Maple's version and location.

It may be similar on UNIX, but I haven't tried that.

It's known that this library's XS part won't work with Maple 7 on Win32. Sigh.

EXPORT

None by default.

METHODS ^

PerlMaple uses AUTOLOAD mechanism so that any Maple functions are also valid methods of your PerlMaple object, even those Maple procedures defined by yourself.

When the ReturnAST attribute is on, all AUTOLOADed methods, along with the eval_cmd method will return a PerlMaple::Expression object constructed from the resulting expression. Because there's a cost involved in constructing an AST from the given Maple expression, so the ReturnAST attribute is off by default.

WARNING: The eval method is now incompatible with that of the first release (0.01). It is AUTOLOADed as the Maple counterpart. So you have to turn to eval_cmd when Maple's eval function can't fit your needs. Sorry.

$obj->new()
$obj->new(RaiseError => 0, PrintError => 1, ReturnAST => 0)

Class constructor. It starts a Maple session if it does not exist. It should be noting that although you're able to create more than one PerlMaple objects, all these maple objects share the same Maple session. So the context of each PerlMaple objects may be corrupted intentionally. If any error occurs, this method will return undef value, and set the internal error buffer which you can read by the error method.

This method also accepts two optional named arguments. When RaiseError is set true, the constructor sets the RaiseError attribute of the new object internally. And it is the same for the PrintError and ReturnAST attributes.

$obj->eval_cmd($command)

This method may be the most important one for the implementation of this class. It evaluates the command stored in the argument, and returns a string containing the result when the ReturnAST attribute is off. (It's off by default.) If an error occurs, it will return undef, and set the internal error buffer which you can read by the error method.

Frankly speaking, most of the time you can use eval method instead of invoking this method directly. However, this method is a bit faster, because any AUTOLOADed method is invoked this one internally. Moreover, there exists something that can only be eval'ed properly by eval_cmd. Here is a small example:

    $maple->eval_cmd(<<'.');
    lc := proc( s, u, t, v )
             description "form a linear combination of the arguments";
             s * u + t * v
    end proc;
    .

If you use eval instead, you will get the following error message:

    `:=` unexpected

That's because "eval" is a normal Maple function and hence you can't use assignment statement as the argument.

When the ReturnAST attribute is on, this method will return a PerlMaple::Expression object constructed from the expression returned by Maple automatically.

$obj->to_ast($maple_expr, ?$verified)

This method is a shortcut for constructing a PerlMaple::Expression instance. For more information on the PerlMaple::Expression class and the second optional argument of this method, please turn to PerlMaple::Expression.

Here is a quick demo to illustrate the power of the PerlMaple::Expression class (you can get many more in the doc for PerlMaple::Expression.

    $ast = $maple->to_ast('[1,2,3]');
    my @list;
    foreach ($ast->ops) {
        push @list, $_->expr;
    }
    # now @list contains numbers 1, 2, and 3.
$obj->error()

It returns the error message issued by the Maple kernel.

ATTRIBUTES ^

All the attributes specified below can be set by passing name-value pairs to the new method.

$obj->PrintError()
$obj->PrintError($new_value)

The PrintError attribute can be used to force errors to generate warnings (using Carp::carp) in addition to returning error codes in the normal way. When set ``on'' (say, a true value), any method which results in an error occurring will cause the PerlMaple to effectively do a carp("PerlMaple error: ", $self->error, " when evaluating \"$exp\"";). Any warnings from the Maple kernel will also be sent to stderr via carp if PrintError is on.

By default, the constructor new sets PrintError ``on''.

$obj->RaiseError()
$obj->RaiseError($new_value)

The RaiseError attribute can be used to force errors to raise exceptions rather than simply return error codes in the normal way. It is ``off'' (say, a false value in Perl) by default. When set ``on'', any method which results in an error will cause the PerlMaple to effectively do a croak("PerlMaple error: ", $self->error, " when evaluating \"$exp\"";).

If you turn RaiseError on then you'd normally turn PrintError off. If PrintError is also on, then the PrintError is done first (naturally).

$obj->ReturnAST()
$obj->ReturnAST($new_value)

The ReturnAST attribute can be used to force the eval_cmd method and hence all AUTOLOADed Maple functions to return a Abstract Syntactic Tree (AST). Because there is a cost to evaluate the to_ast method every time, so this attribute is off by default.

INTERNAL FUNCTIONS ^

maple_error

Returns the raw error message issued by the Maple kernel.

maple_warning

Returns the raw warning message returned by the Maple kernel.

maple_eval

Raw XS C method that evaluates any Maple commands.

maple_result

Returns the raw output of the Maple kernel.

maple_start

Starts the global Maple kernel. (No that all PerlMaple objects share the same Maple engine, so preventing context clashes is the duty of the user.

maple_success

Indicates whether the last Maple evaluation is successful.

CODE COVERAGE ^

I use Devel::Cover to test the code coverage of my tests, below is the Devel::Cover report on this module's test suite (version 0.06):

    ---------------------------- ------ ------ ------ ------ ------ ------ ------
    File                           stmt   bran   cond    sub    pod   time  total
    ---------------------------- ------ ------ ------ ------ ------ ------ ------
    blib/lib/PerlMaple.pm          92.4   80.8   66.7  100.0  100.0  100.0   89.9
    ...b/PerlMaple/Expression.pm   98.7   88.9   66.7  100.0  100.0    0.0   94.6
    Total                          95.9   85.5   66.7  100.0  100.0  100.0   92.5
    ---------------------------- ------ ------ ------ ------ ------ ------ ------

BUGS ^

At this point, every PerlMaple objects are merely a bunch of options (e.g. PrintError, RaiseError, and ReturnAST). They actually share the same Maple engine for performance reasons. So the evaluating contexts for each PerlMaple objects may corrupt together. So please don't store permanent values in Maple variables, avoid reference Maple special variables, like %, %%, and don't trust the Maple contexts. Since they may be changed accidentally by other PerlMaple objects, even those used by PerlMaple::Expression instances, in the duration.

TODO ^

REPOSITORY ^

You can always get the latest version from the following SVN repository:

https://svn.berlios.de/svnroot/repos/win32maple

If you want a committer bit, please let me know.

SEE ALSO ^

PerlMaple::Expression, http://www.maplesoft.com.

AUTHOR ^

Agent Zhang, <agentzh@gmail.com>

COPYRIGHT AND LICENSE ^

Copyright (C) 2005-2006 Agent Zhang

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

syntax highlighting: