package bigrat;
-require 5.005;
+use 5.006;
-$VERSION = '0.08';
+$VERSION = '0.23';
require Exporter;
-@ISA = qw( Exporter );
-@EXPORT_OK = qw( );
-@EXPORT = qw( inf NaN );
+@ISA = qw( bigint );
+@EXPORT_OK = qw( PI e bpi bexp );
+@EXPORT = qw( inf NaN );
use strict;
+use overload;
+require bigint; # no "use" to avoid callind import
##############################################################################
+BEGIN
+ {
+ *inf = \&bigint::inf;
+ *NaN = \&bigint::NaN;
+ }
+
# These are all alike, and thus faked by AUTOLOAD
my @faked = qw/round_mode accuracy precision div_scale/;
Carp::croak ("Can't call bigrat\-\>$name, not a valid method");
}
-sub upgrade
+sub unimport
{
- my $self = shift;
- no strict 'refs';
-# if (defined $_[0])
-# {
-# $Math::BigInt::upgrade = $_[0];
-# $Math::BigFloat::upgrade = $_[0];
-# }
- return $Math::BigInt::upgrade;
+ $^H{bigrat} = undef; # no longer in effect
+ overload::remove_constant('binary','','float','','integer');
+ }
+
+sub in_effect
+ {
+ my $level = shift || 0;
+ my $hinthash = (caller($level))[10];
+ $hinthash->{bigrat};
+ }
+
+#############################################################################
+# the following two routines are for Perl 5.9.4 or later and are lexical
+
+sub _hex
+ {
+ return CORE::hex($_[0]) unless in_effect(1);
+ my $i = $_[0];
+ $i = '0x'.$i unless $i =~ /^0x/;
+ Math::BigInt->new($i);
+ }
+
+sub _oct
+ {
+ return CORE::oct($_[0]) unless in_effect(1);
+ my $i = $_[0];
+ return Math::BigInt->from_oct($i) if $i =~ /^0[0-7]/;
+ Math::BigInt->new($i);
}
sub import
# see also bignum->import() for additional comments
+ $^H{bigrat} = 1; # we are in effect
+
+ my ($hex,$oct);
+ # for newer Perls always override hex() and oct() with a lexical version:
+ if ($] > 5.009004)
+ {
+ $oct = \&_oct;
+ $hex = \&_hex;
+ }
# some defaults
- my $lib = ''; my $upgrade = 'Math::BigFloat';
+ my $lib = ''; my $lib_kind = 'try'; my $upgrade = 'Math::BigFloat';
my @import = ( ':constant' ); # drive it w/ constant
my @a = @_; my $l = scalar @_; my $j = 0;
my $s = 2; $s = 1 if @a-$j < 2; # avoid "can not modify non-existant..."
splice @a, $j, $s; $j -= $s;
}
- elsif ($_[$i] =~ /^(l|lib)$/)
+ elsif ($_[$i] =~ /^(l|lib|try|only)$/)
{
# this causes a different low lib to take care...
+ $lib_kind = $1; $lib_kind = 'lib' if $lib_kind eq 'l';
$lib = $_[$i+1] || '';
my $s = 2; $s = 1 if @a-$j < 2; # avoid "can not modify non-existant..."
splice @a, $j, $s; $j -= $s; $i++;
$trace = 1;
splice @a, $j, 1; $j --;
}
- else
+ elsif ($_[$i] eq 'hex')
+ {
+ splice @a, $j, 1; $j --;
+ $hex = \&bigint::_hex_global;
+ }
+ elsif ($_[$i] eq 'oct')
+ {
+ splice @a, $j, 1; $j --;
+ $oct = \&bigint::_oct_global;
+ }
+ elsif ($_[$i] !~ /^(PI|e|bpi|bexp)\z/)
{
die ("unknown option $_[$i]");
}
require Math::BigInt if $_lite == 0; # not already loaded?
$class = 'Math::BigInt'; # regardless of MBIL or not
}
- push @import, 'lib' => $lib if $lib ne '';
+ push @import, $lib_kind => $lib if $lib ne '';
# Math::BigInt::Trace or plain Math::BigInt
$class->import(@import, upgrade => $upgrade);
print "Math::BigRat\t\t v$Math::BigRat::VERSION\n";
exit;
}
- $self->export_to_level(1,$self,@a); # export inf and NaN
+
+ # Take care of octal/hexadecimal constants
+ overload::constant binary => sub { bigint::_binary_constant(shift) };
+
+ # if another big* was already loaded:
+ my ($package) = caller();
+
+ no strict 'refs';
+ if (!defined *{"${package}::inf"})
+ {
+ $self->export_to_level(1,$self,@a); # export inf and NaN
+ }
+ {
+ no warnings 'redefine';
+ *CORE::GLOBAL::oct = $oct if $oct;
+ *CORE::GLOBAL::hex = $hex if $hex;
+ }
}
-sub inf () { Math::BigInt->binf(); }
-sub NaN () { Math::BigInt->bnan(); }
+sub PI () { Math::BigFloat->new('3.141592653589793238462643383279502884197'); }
+sub e () { Math::BigFloat->new('2.718281828459045235360287471352662497757'); }
+
+sub bpi ($) { local $Math::BigFloat::upgrade; Math::BigFloat::bpi(@_); }
+
+sub bexp ($$)
+ {
+ local $Math::BigFloat::upgrade;
+ my $x = Math::BigFloat->new($_[0]); $x->bexp($_[1]);
+ }
1;
use bigrat;
- $x = 2 + 4.5,"\n"; # BigFloat 6.5
+ print 2 + 4.5,"\n"; # BigFloat 6.5
print 1/3 + 1/4,"\n"; # produces 7/12
+ {
+ no bigrat;
+ print 1/3,"\n"; # 0.33333...
+ }
+
+ # Note that this will make hex() and oct() be globally overriden:
+ use bigrat qw/hex oct/;
+ print hex("0x1234567890123490"),"\n";
+ print oct("01234567890123490"),"\n";
+
=head1 DESCRIPTION
All operators (including basic math operations) are overloaded. Integer and
You can change this by using:
- use bigrat lib => 'BitVect';
+ use bignum lib => 'GMP';
The following would first try to find Math::BigInt::Foo, then
Math::BigInt::Bar, and when this also fails, revert to Math::BigInt::Calc:
use bigrat lib => 'Foo,Math::BigInt::Bar';
+Using C<lib> warns if none of the specified libraries can be found and
+L<Math::BigInt> did fall back to one of the default libraries.
+To supress this warning, use C<try> instead:
+
+ use bignum try => 'GMP';
+
+If you want the code to die instead of falling back, use C<only> instead:
+
+ use bignum only => 'GMP';
+
Please see respective module documentation for further details.
=head2 Sign
the fxxx() notation, though. This makes you independed on the fact that the
underlying object might morph into a different class than BigFloat.
-=head2 Caveat
+=over 2
+
+=item inf()
+
+A shortcut to return Math::BigInt->binf(). Useful because Perl does not always
+handle bareword C<inf> properly.
+
+=item NaN()
+
+A shortcut to return Math::BigInt->bnan(). Useful because Perl does not always
+handle bareword C<NaN> properly.
+
+=item e
+
+ # perl -Mbigrat=e -wle 'print e'
+
+Returns Euler's number C<e>, aka exp(1).
+
+=item PI
+
+ # perl -Mbigrat=PI -wle 'print PI'
+
+Returns PI.
+
+=item bexp()
+
+ bexp($power,$accuracy);
+
+
+Returns Euler's number C<e> raised to the appropriate power, to
+the wanted accuracy.
+
+Example:
+
+ # perl -Mbigrat=bexp -wle 'print bexp(1,80)'
+
+=item bpi()
+
+ bpi($accuracy);
+
+Returns PI to the wanted accuracy.
+
+Example:
+
+ # perl -Mbigrat=bpi -wle 'print bpi(80)'
+
+=item upgrade()
+
+Return the class that numbers are upgraded to, is in fact returning
+C<$Math::BigInt::upgrade>.
+
+=item in_effect()
+
+ use bigrat;
+
+ print "in effect\n" if bigrat::in_effect; # true
+ {
+ no bigrat;
+ print "in effect\n" if bigrat::in_effect; # false
+ }
+
+Returns true or false if C<bigrat> is in effect in the current scope.
+
+This method only works on Perl v5.9.4 or later.
+
+=back
+
+=head2 MATH LIBRARY
+
+Math with the numbers is done (by default) by a module called
+
+=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.
perl -Mbigrat=a,50 -le 'print sqrt(20)'
+Note that setting precision and accurary at the same time is not possible.
+
=item p or precision
This sets the precision for all math operations. The argument can be any
perl -Mbigrat=p,-50 -le 'print sqrt(20)'
+Note that setting precision and accurary at the same time is not possible.
+
=item t or trace
This enables a trace mode and is primarily for debugging bignum or
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 ;)
+line. This means the following does not work:
+
+ perl -Mbignum=l,GMP,Pari -e 'print 2 ** 512'
+
+This will be hopefully fixed soon ;)
+
+=item hex
+
+Override the built-in hex() method with a version that can handle big
+integers. Note that under Perl v5.9.4 or ealier, this will be global
+and cannot be disabled with "no bigint;".
+
+=item oct
+
+Override the built-in oct() method with a version that can handle big
+integers. Note that under Perl v5.9.4 or ealier, this will be global
+and cannot be disabled with "no bigint;".
=item v or version
perl -Mbigrat=v
+=back
+
+=head1 CAVAETS
+
+=over 2
+
+=item in_effect()
+
+This method only works on Perl v5.9.4 or later.
+
+=item hex()/oct()
+
+C<bigint> overrides these routines with versions that can also handle
+big integer values. Under Perl prior to version v5.9.4, however, this
+will not happen unless you specifically ask for it with the two
+import tags "hex" and "oct" - and then it will be global and cannot be
+disabled inside a scope with "no bigint":
+
+ use bigint qw/hex oct/;
+
+ print hex("0x1234567890123456");
+ {
+ no bigint;
+ print hex("0x1234567890123456");
+ }
+
+The second call to hex() will warn about a non-portable constant.
+
+Compare this to:
+
+ use bigint;
+
+ # will warn only under Perl older than v5.9.4
+ print hex("0x1234567890123456");
+
+=back
+
=head1 EXAMPLES
perl -Mbigrat -le 'print sqrt(33)'
perl -Mbigrat -le 'print 4.5+2*255'
perl -Mbigrat -le 'print 3/7 + 5/7 + 8/3'
perl -Mbigrat -le 'print 12->is_odd()';
+ perl -Mbignum=l,GMP -le 'print 7 ** 7777'
=head1 LICENSE
=head1 AUTHORS
-(C) by Tels L<http://bloodgate.com/> in early 2002 - 2005.
+(C) by Tels L<http://bloodgate.com/> in early 2002 - 2007.
=cut