View of /trunk/pg/lib/Parser/List/Matrix.pm

    1 #########################################################################
    2 #
    3 #  Implements the Matrix class.
    4 #
    5 package Parser::List::Matrix;
    6 use strict;
    7 our @ISA = qw(Parser::List);
    8 
    9 #
   10 #  The main checks are all done in the List object.
   11 #  Here, we just convert the entry types from points or
   12 #    vectors to matrices (hack) with appropriate parens.
   13 #
   14 sub _check {
   15   my $self = shift;
   16   my $matrix = $self->{equation}{context}{lists}{Matrix};
   17   $self->{open} = $matrix->{open}; $self->{close} = $matrix->{close};
   18   if ($self->{entryType}{name} ne 'Matrix') {
   19     foreach my $x (@{$self->{coords}})
   20       {$x->makeMatrix($self->{type}{name},$self->{open},$self->{close})}
   21   }
   22   foreach my $x (@{$self->{coords}}) {
   23     $self->{equation}->Error("Entries in a Matrix must be Numbers or Lists of Numbers")
   24       unless ($x->type =~ m/Number|Matrix/);
   25   }
   26 }
   27 
   28 #
   29 #  Handle a 2-dimensional matrix as a special case, using
   30 #  LaTeX's \array command.
   31 #
   32 sub TeX {
   33   my ($self,$precedence) = @_;
   34   return $self->SUPER::TeX(@_) unless $self->entryType->{entryType};
   35   my ($open,$close) = ($self->{open},$self->{close});
   36   $open = '\{' if $open eq '{'; $close = '\}' if $close eq '}';
   37   my $TeX = ''; my @entries = (); my $d;
   38   foreach my $row (@{$self->coords}) {
   39     foreach my $x (@{$row->coords}) {push(@entries,$x->TeX)}
   40     $TeX .= join(' &',@entries) . '\cr'."\n";
   41     $d = scalar(@entries); @entries = ();
   42   }
   43   $TeX = '\begin{array}{'.($self->{array_template} || ('c'x$d)).'}'."\n".$TeX.'\end{array}';
   44   return $TeX unless $open || $close;
   45   $open  = "." if $close && !$open;
   46   $close = "." if $open && !$close;
   47   return '\left'.$open.$TeX.'\right'.$close;
   48 }
   49 
   50 #
   51 #  Recursively handle the rows, but only enclose in brackets
   52 #  to form reference to array of (references to arrays of ...) entries
   53 #
   54 sub perl {
   55   my $self = shift; my $parens = shift; my $matrix = shift;
   56   my $perl; my @p = ();
   57   foreach my $x (@{$self->{coords}}) {push(@p,$x->perl(0,1))}
   58   if ($matrix) {
   59     $perl = '['.join(',',@p).']';
   60   } else {
   61     $perl = $self->Package($self->type).'->new('.join(',',@p).')';
   62     $perl = '('.$perl.')' if $parens;
   63   }
   64   return $perl;
   65 }
   66 
   67 #########################################################################
   68 
   69 1;