Math-Algebra-Symbols

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lib/Math/Algebra/Symbols/Sum.pm  view on Meta::CPAN

 }


=head3 st

Get the single term from a sum containing just one term

=cut


sub st($)
 {my ($a) = @_;
  return (values(%{$a->{t}}))[0] if scalar(keys(%{$a->{t}})) == 1;
  undef;
 }


=head3 negate

Multiply each term in a sum by -1

lib/Math/Algebra/Symbols/Sum.pm  view on Meta::CPAN

 }


=head3 re

Real part of a complex sum

=cut


sub re($)
 {my ($A) = @_;
  $A = newFromString("$A") unless ref($A) eq __PACKAGE__;
  my @r;
  for my $a($A->t)
   {next if $a->i == 1;
    push @r, $a;
   }
  sigma(@r);
 }


=head3 im

Imaginary part of a complex sum

=cut


sub im($)
 {my ($A) = @_;
  $A = newFromString("$A") unless ref($A) eq __PACKAGE__;
  my @r;
  for my $a($A->t)
   {next if $a->i == 0;
    push @r, $a;
   }
  $mI->multiply(sigma(@r));
 }

lib/Math/Algebra/Symbols/Sum.pm  view on Meta::CPAN

 }


=head3 id

Get Id of sum: each sum has a unique identifying number.

=cut


sub id($)
 {my ($t) = @_;
  $t->{id} or die "Sum $t not yet finalized";
  $t->{id};
 }


=head3 zz

Check sum finalized.  See: L</z>.

=cut


sub zz($)
 {my ($t) = @_;
  $t->{z} or die "Sum $t not yet finalized";
  print $t->{z}, "\n";
  $t;
 }


=head3 z

Finalize creation of the sum: Once a sum has been finalized it becomes

lib/Math/Algebra/Symbols/Term.pm  view on Meta::CPAN

On get: returns the power of a variable, or zero if the variable is not
present in the term.

On set: Sets the power of a variable. If the power is zero, removes the
variable from the term. =cut

=cut


sub vp($$;$)
 {my ($t, $v) = @_;
# $v =~ /^[a-z]+$/i or die "Bad variable name $v";

  return exists($t->{v}{$v}) ? $t->{v}{$v} : 0 if @_ == 2;

  my $p = ($_[2] == 1 ? $_[2] : intCheck($_[2], 'vp'));
  $t->{v}{$v} = $p   if $p;
  delete $t->{v}{$v} unless $p;
  $t;
 }

lib/Math/Algebra/Symbols/Term.pm  view on Meta::CPAN

 }


=head3 id

Get Id of a term

=cut


sub id($)
 {my ($t) = @_;
  $t->{id} or die "Term $t not yet finalized";
  $t->{id};
 }


=head3 zz

# Check term finalized

=cut


sub zz($)
 {my ($t) = @_;
  $t->{z} or die "Term $t not yet finalized";
  $t;
 }


=head3 z

Finalize creation of the term. Once a term has been finalized, it
becomes readonly, which allows optimization to be performed.