package bigrat;
require 5.005;
-$VERSION = '0.04';
-use Exporter;
-@ISA = qw( Exporter );
-@EXPORT_OK = qw( );
+$VERSION = '0.08';
+require Exporter;
+@ISA = qw( Exporter );
+@EXPORT_OK = qw( );
+@EXPORT = qw( inf NaN );
use strict;
{
Math::BigInt->$name($_[0]);
Math::BigFloat->$name($_[0]);
+ return Math::BigRat->$name($_[0]);
}
return Math::BigInt->$name();
};
# see also bignum->import() for additional comments
# some defaults
- my $lib = 'Calc'; my $upgrade = 'Math::BigFloat';
+ my $lib = ''; my $upgrade = 'Math::BigFloat';
my @import = ( ':constant' ); # drive it w/ constant
my @a = @_; my $l = scalar @_; my $j = 0;
# this causes a different low lib to take care...
$lib = $_[$i+1] || '';
my $s = 2; $s = 1 if @a-$j < 2; # avoid "can not modify non-existant..."
- splice @a, $j, $s; $j -= $s;
+ splice @a, $j, $s; $j -= $s; $i++;
+ }
+ elsif ($_[$i] =~ /^(a|accuracy)$/)
+ {
+ $a = $_[$i+1];
+ my $s = 2; $s = 1 if @a-$j < 2; # avoid "can not modify non-existant..."
+ splice @a, $j, $s; $j -= $s; $i++;
+ }
+ elsif ($_[$i] =~ /^(p|precision)$/)
+ {
+ $p = $_[$i+1];
+ my $s = 2; $s = 1 if @a-$j < 2; # avoid "can not modify non-existant..."
+ splice @a, $j, $s; $j -= $s; $i++;
}
elsif ($_[$i] =~ /^(v|version)$/)
{
require Math::BigInt if $_lite == 0; # not already loaded?
$class = 'Math::BigInt'; # regardless of MBIL or not
}
+ push @import, 'lib' => $lib if $lib ne '';
# Math::BigInt::Trace or plain Math::BigInt
- $class->import(@import, upgrade => $upgrade, lib => $lib);
+ $class->import(@import, upgrade => $upgrade);
require Math::BigFloat;
Math::BigFloat->import( upgrade => 'Math::BigRat', ':constant' );
require Math::BigRat;
+
+ bigrat->accuracy($a) if defined $a;
+ bigrat->precision($p) if defined $p;
if ($ver)
{
print "bigrat\t\t\t v$VERSION\n";
print "Math::BigRat\t\t v$Math::BigRat::VERSION\n";
exit;
}
+ $self->export_to_level(1,$self,@a); # export inf and NaN
}
+sub inf () { Math::BigInt->binf(); }
+sub NaN () { Math::BigInt->bnan(); }
+
1;
__END__
=head1 NAME
-bigrat - Transparent BigNumber/BigRationale support for Perl
+bigrat - Transparent BigNumber/BigRational support for Perl
=head1 SYNOPSIS
Other than L<bignum>, this module upgrades to Math::BigRat, meaning that
instead of 2.5 you will get 2+1/2 as output.
-=head2 MODULES USED
+=head2 Modules Used
C<bigrat> is just a thin wrapper around various modules of the Math::BigInt
family. Think of it as the head of the family, who runs the shop, and orders
Math::BigFloat
Math::BigRat
-=head2 MATH LIBRARY
+=head2 Math Library
Math with the numbers is done (by default) by a module called
Math::BigInt::Calc. This is equivalent to saying:
Please see respective module documentation for further details.
-=head2 SIGN
+=head2 Sign
-The sign is either '+', '-', 'NaN', '+inf' or '-inf' and stored seperately.
+The sign is either '+', '-', 'NaN', '+inf' or '-inf'.
A sign of 'NaN' is used to represent the result when input arguments are not
numbers or as a result of 0/0. '+inf' and '-inf' represent plus respectively
minus infinity. You will get '+inf' when dividing a positive number by 0, and
'-inf' when dividing any negative number by 0.
-=head2 METHODS
+=head2 Methods
Since all numbers are not objects, you can use all functions that are part of
the BigInt or BigFloat API. It is wise to use only the bxxx() notation, and not
the fxxx() notation, though. This makes you independed on the fact that the
underlying object might morph into a different class than BigFloat.
+=head2 Cavaet
+
+But a warning is in order. When using the following to make a copy of a number,
+only a shallow copy will be made.
+
+ $x = 9; $y = $x;
+ $x = $y = 7;
+
+If you want to make a real copy, use the following:
+
+ $y = $x->copy();
+
+Using the copy or the original with overloaded math is okay, e.g. the
+following work:
+
+ $x = 9; $y = $x;
+ print $x + 1, " ", $y,"\n"; # prints 10 9
+
+but calling any method that modifies the number directly will result in
+B<both> the original and the copy beeing destroyed:
+
+ $x = 9; $y = $x;
+ print $x->badd(1), " ", $y,"\n"; # prints 10 10
+
+ $x = 9; $y = $x;
+ print $x->binc(1), " ", $y,"\n"; # prints 10 10
+
+ $x = 9; $y = $x;
+ print $x->bmul(2), " ", $y,"\n"; # prints 18 18
+
+Using methods that do not modify, but testthe contents works:
+
+ $x = 9; $y = $x;
+ $z = 9 if $x->is_zero(); # works fine
+
+See the documentation about the copy constructor and C<=> in overload, as
+well as the documentation in BigInt for further details.
+
+=head2 Options
+
+bignum recognizes some options that can be passed while loading it via use.
+The options can (currently) be either a single letter form, or the long form.
+The following options exist:
+
+=over 2
+
+=item a or accuracy
+
+This sets the accuracy for all math operations. The argument must be greater
+than or equal to zero. See Math::BigInt's bround() function for details.
+
+ perl -Mbigrat=a,50 -le 'print sqrt(20)'
+
+=item p or precision
+
+This sets the precision for all math operations. The argument can be any
+integer. Negative values mean a fixed number of digits after the dot, while
+a positive value rounds to this digit left from the dot. 0 or 1 mean round to
+integer. See Math::BigInt's bfround() function for details.
+
+ perl -Mbigrat=p,-50 -le 'print sqrt(20)'
+
+=item t or trace
+
+This enables a trace mode and is primarily for debugging bignum or
+Math::BigInt/Math::BigFloat.
+
+=item l or lib
+
+Load a different math lib, see L<MATH LIBRARY>.
+
+ perl -Mbigrat=l,GMP -e 'print 2 ** 512'
+
+Currently there is no way to specify more than one library on the command
+line. This will be hopefully fixed soon ;)
+
+=item v or version
+
+This prints out the name and version of all modules used and then exits.
+
+ perl -Mbigrat=v
+
=head1 EXAMPLES
perl -Mbigrat -le 'print sqrt(33)'
=head1 AUTHORS
-(C) by Tels L<http://bloodgate.com/> in early 2002.
+(C) by Tels L<http://bloodgate.com/> in early 2002 - 2005.
=cut
https://perl5.git.perl.org / perl5.git / blobdiff