7 @EXPORT_OK = qw( PI e );
8 @EXPORT = qw( inf NaN );
13 ##############################################################################
15 # These are all alike, and thus faked by AUTOLOAD
17 my @faked = qw/round_mode accuracy precision div_scale/;
18 use vars qw/$VERSION $AUTOLOAD $_lite/; # _lite for testsuite
24 $name =~ s/.*:://; # split package
26 foreach my $n (@faked)
30 *{"bigint::$name"} = sub
36 return Math::BigInt->$name($_[0]);
38 return Math::BigInt->$name();
44 # delayed load of Carp and avoid recursion
46 Carp::croak ("Can't call bigint\-\>$name, not a valid method");
51 $Math::BigInt::upgrade;
56 # this takes a binary/hexadecimal/octal constant string and returns it
57 # as string suitable for new. Basically it converts octal to decimal, and
58 # passes every thing else unmodified back.
61 return Math::BigInt->new($string) if $string =~ /^0[bx]/;
63 # so it must be an octal constant
64 Math::BigInt->from_oct($string);
69 # this takes a floating point constant string and returns it truncated to
70 # integer. For instance, '4.5' => '4', '1.234e2' => '123' etc
73 # some simple cases first
74 return $float if ($float =~ /^[+-]?[0-9]+$/); # '+123','-1','0' etc
76 if ($float =~ /^[+-]?[0-9]+\.?[eE]\+?[0-9]+$/); # 123e2, 123.e+2
77 return '0' if ($float =~ /^[+-]?[0]*\.[0-9]+$/); # .2, 0.2, -.1
78 if ($float =~ /^[+-]?[0-9]+\.[0-9]*$/) # 1., 1.23, -1.2 etc
83 my ($mis,$miv,$mfv,$es,$ev) = Math::BigInt::_split($float);
84 return $float if !defined $mis; # doesn't look like a number to me
86 my $sign = $$mis; $sign = '' if $sign eq '+';
89 # ignore fraction part entirely
90 if ($ec >= length($$miv)) # 123.23E-4
94 return $sign . substr ($$miv,0,length($$miv)-$ec); # 1234.45E-2 = 12
97 if ($ec >= length($$mfv))
100 return $sign.$$miv.$$mfv if $ec == 0; # 123.45E+2 => 12345
101 return $sign.$$miv.$$mfv.'E'.$ec; # 123.45e+3 => 12345e1
103 $mfv = substr($$mfv,0,$ec);
104 $sign.$$miv.$mfv; # 123.45e+1 => 1234
109 $^H{bigint} = undef; # no longer in effect
110 overload::remove_constant('binary','','float','','integer');
115 my $level = shift || 0;
116 my $hinthash = (caller($level))[10];
120 #############################################################################
121 # the following two routines are for "use bigint qw/hex oct/;":
126 $i = '0x'.$i unless $i =~ /^0x/;
127 Math::BigInt->new($i);
133 return Math::BigInt->from_oct($i) if $i =~ /^0[0-7]/;
134 Math::BigInt->new($i);
137 #############################################################################
138 # the following two routines are for Perl 5.9.4 or later and are lexical
142 return CORE::hex($_[0]) unless in_effect(1);
144 $i = '0x'.$i unless $i =~ /^0x/;
145 Math::BigInt->new($i);
150 return CORE::oct($_[0]) unless in_effect(1);
152 return Math::BigInt->from_oct($i) if $i =~ /^0[0-7]/;
153 Math::BigInt->new($i);
160 $^H{bigint} = 1; # we are in effect
163 # for newer Perls always override hex() and oct() with a lexical version:
170 my $lib = ''; my $lib_kind = 'try';
172 my @import = ( ':constant' ); # drive it w/ constant
173 my @a = @_; my $l = scalar @_; my $j = 0;
174 my ($ver,$trace); # version? trace?
175 my ($a,$p); # accuracy, precision
176 for ( my $i = 0; $i < $l ; $i++,$j++ )
178 if ($_[$i] =~ /^(l|lib|try|only)$/)
180 # this causes a different low lib to take care...
181 $lib_kind = $1; $lib_kind = 'lib' if $lib_kind eq 'l';
182 $lib = $_[$i+1] || '';
183 my $s = 2; $s = 1 if @a-$j < 2; # avoid "can not modify non-existant..."
184 splice @a, $j, $s; $j -= $s; $i++;
186 elsif ($_[$i] =~ /^(a|accuracy)$/)
189 my $s = 2; $s = 1 if @a-$j < 2; # avoid "can not modify non-existant..."
190 splice @a, $j, $s; $j -= $s; $i++;
192 elsif ($_[$i] =~ /^(p|precision)$/)
195 my $s = 2; $s = 1 if @a-$j < 2; # avoid "can not modify non-existant..."
196 splice @a, $j, $s; $j -= $s; $i++;
198 elsif ($_[$i] =~ /^(v|version)$/)
201 splice @a, $j, 1; $j --;
203 elsif ($_[$i] =~ /^(t|trace)$/)
206 splice @a, $j, 1; $j --;
208 elsif ($_[$i] eq 'hex')
210 splice @a, $j, 1; $j --;
211 $hex = \&_hex_global;
213 elsif ($_[$i] eq 'oct')
215 splice @a, $j, 1; $j --;
216 $oct = \&_oct_global;
218 elsif ($_[$i] !~ /^(PI|e)\z/)
220 die ("unknown option $_[$i]");
224 $_lite = 0; # using M::BI::L ?
227 require Math::BigInt::Trace; $class = 'Math::BigInt::Trace';
231 # see if we can find Math::BigInt::Lite
232 if (!defined $a && !defined $p) # rounding won't work to well
234 eval 'require Math::BigInt::Lite;';
237 @import = ( ); # :constant in Lite, not MBI
238 Math::BigInt::Lite->import( ':constant' );
239 $_lite= 1; # signal okay
242 require Math::BigInt if $_lite == 0; # not already loaded?
243 $class = 'Math::BigInt'; # regardless of MBIL or not
245 push @import, $lib_kind => $lib if $lib ne '';
246 # Math::BigInt::Trace or plain Math::BigInt
247 $class->import(@import);
249 bigint->accuracy($a) if defined $a;
250 bigint->precision($p) if defined $p;
253 print "bigint\t\t\t v$VERSION\n";
254 print "Math::BigInt::Lite\t v$Math::BigInt::Lite::VERSION\n" if $_lite;
255 print "Math::BigInt\t\t v$Math::BigInt::VERSION";
256 my $config = Math::BigInt->config();
257 print " lib => $config->{lib} v$config->{lib_version}\n";
260 # we take care of floating point constants, since BigFloat isn't available
261 # and BigInt doesn't like them:
262 overload::constant float => sub { Math::BigInt->new( _float_constant(shift) ); };
263 # Take care of octal/hexadecimal constants
264 overload::constant binary => sub { _binary_constant(shift) };
266 # if another big* was already loaded:
267 my ($package) = caller();
270 if (!defined *{"${package}::inf"})
272 $self->export_to_level(1,$self,@a); # export inf and NaN, e and PI
275 no warnings 'redefine';
276 *CORE::GLOBAL::oct = $oct if $oct;
277 *CORE::GLOBAL::hex = $hex if $hex;
281 sub inf () { Math::BigInt::binf(); }
282 sub NaN () { Math::BigInt::bnan(); }
283 sub PI () { Math::BigInt->new(3); }
284 sub e () { Math::BigInt->new(2); }
292 bigint - Transparent BigInteger support for Perl
298 $x = 2 + 4.5,"\n"; # BigInt 6
299 print 2 ** 512,"\n"; # really is what you think it is
300 print inf + 42,"\n"; # inf
301 print NaN * 7,"\n"; # NaN
302 print hex("0x1234567890123490"),"\n"; # Perl v5.9.4 or later
306 print 2 ** 256,"\n"; # a normal Perl scalar now
309 # Note that this will be global:
310 use bigint qw/hex oct/;
311 print hex("0x1234567890123490"),"\n";
312 print oct("01234567890123490"),"\n";
316 All operators (including basic math operations) are overloaded. Integer
317 constants are created as proper BigInts.
319 Floating point constants are truncated to integer. All parts and results of
320 expressions are also truncated.
322 Unlike L<integer>, this pragma creates integer constants that are only
323 limited in their size by the available memory and CPU time.
325 =head2 use integer vs. use bigint
327 There is one small difference between C<use integer> and C<use bigint>: the
328 former will not affect assignments to variables and the return value of
329 some functions. C<bigint> truncates these results to integer too:
331 # perl -Minteger -wle 'print 3.2'
333 # perl -Minteger -wle 'print 3.2 + 0'
335 # perl -Mbigint -wle 'print 3.2'
337 # perl -Mbigint -wle 'print 3.2 + 0'
340 # perl -Mbigint -wle 'print exp(1) + 0'
342 # perl -Mbigint -wle 'print exp(1)'
344 # perl -Minteger -wle 'print exp(1)'
346 # perl -Minteger -wle 'print exp(1) + 0'
349 In practice this makes seldom a difference as B<parts and results> of
350 expressions will be truncated anyway, but this can, for instance, affect the
351 return value of subroutines:
353 sub three_integer { use integer; return 3.2; }
354 sub three_bigint { use bigint; return 3.2; }
356 print three_integer(), " ", three_bigint(),"\n"; # prints "3.2 3"
360 bigint recognizes some options that can be passed while loading it via use.
361 The options can (currently) be either a single letter form, or the long form.
362 The following options exist:
368 This sets the accuracy for all math operations. The argument must be greater
369 than or equal to zero. See Math::BigInt's bround() function for details.
371 perl -Mbigint=a,2 -le 'print 12345+1'
373 Note that setting precision and accurary at the same time is not possible.
377 This sets the precision for all math operations. The argument can be any
378 integer. Negative values mean a fixed number of digits after the dot, and
379 are <B>ignored</B> since all operations happen in integer space.
380 A positive value rounds to this digit left from the dot. 0 or 1 mean round to
381 integer and are ignore like negative values.
383 See Math::BigInt's bfround() function for details.
385 perl -Mbignum=p,5 -le 'print 123456789+123'
387 Note that setting precision and accurary at the same time is not possible.
391 This enables a trace mode and is primarily for debugging bigint or
396 Override the build-in hex() method with a version that can handle big
397 integers. Note that under Perl v5.9.4 or ealier, this will be global
398 and cannot be disabled with "no bigint;".
402 Override the build-in oct() method with a version that can handle big
403 integers. Note that under Perl v5.9.4 or ealier, this will be global
404 and cannot be disabled with "no bigint;".
406 =item l, lib, try or only
408 Load a different math lib, see L<Math Library>.
410 perl -Mbigint=lib,GMP -e 'print 2 ** 512'
411 perl -Mbigint=try,GMP -e 'print 2 ** 512'
412 perl -Mbigint=only,GMP -e 'print 2 ** 512'
414 Currently there is no way to specify more than one library on the command
415 line. This means the following does not work:
417 perl -Mbignum=l,GMP,Pari -e 'print 2 ** 512'
419 This will be hopefully fixed soon ;)
423 This prints out the name and version of all modules used and then exits.
431 Math with the numbers is done (by default) by a module called
432 Math::BigInt::Calc. This is equivalent to saying:
434 use bigint lib => 'Calc';
436 You can change this by using:
438 use bignum lib => 'GMP';
440 The following would first try to find Math::BigInt::Foo, then
441 Math::BigInt::Bar, and when this also fails, revert to Math::BigInt::Calc:
443 use bigint lib => 'Foo,Math::BigInt::Bar';
445 Using C<lib> warns if none of the specified libraries can be found and
446 L<Math::BigInt> did fall back to one of the default libraries.
447 To supress this warning, use C<try> instead:
449 use bignum try => 'GMP';
451 If you want the code to die instead of falling back, use C<only> instead:
453 use bignum only => 'GMP';
455 Please see respective module documentation for further details.
457 =head2 Internal Format
459 The numbers are stored as objects, and their internals might change at anytime,
460 especially between math operations. The objects also might belong to different
461 classes, like Math::BigInt, or Math::BigInt::Lite. Mixing them together, even
462 with normal scalars is not extraordinary, but normal and expected.
464 You should not depend on the internal format, all accesses must go through
465 accessor methods. E.g. looking at $x->{sign} is not a good idea since there
466 is no guaranty that the object in question has such a hash key, nor is a hash
471 The sign is either '+', '-', 'NaN', '+inf' or '-inf'.
472 You can access it with the sign() method.
474 A sign of 'NaN' is used to represent the result when input arguments are not
475 numbers or as a result of 0/0. '+inf' and '-inf' represent plus respectively
476 minus infinity. You will get '+inf' when dividing a positive number by 0, and
477 '-inf' when dividing any negative number by 0.
481 Since all numbers are now objects, you can use all functions that are part of
482 the BigInt API. You can only use the bxxx() notation, and not the fxxx()
489 A shortcut to return Math::BigInt->binf(). Useful because Perl does not always
490 handle bareword C<inf> properly.
494 A shortcut to return Math::BigInt->bnan(). Useful because Perl does not always
495 handle bareword C<NaN> properly.
499 Returns Euler's number C<e>, aka exp(1), to the given number of digits.
503 Returns PI to the given number of digits.
507 Return the class that numbers are upgraded to, is in fact returning
508 C<$Math::BigInt::upgrade>.
514 print "in effect\n" if bigint::in_effect; # true
517 print "in effect\n" if bigint::in_effect; # false
520 Returns true or false if C<bigint> is in effect in the current scope.
522 This method only works on Perl v5.9.4 or later.
528 Math with the numbers is done (by default) by a module called
532 But a warning is in order. When using the following to make a copy of a number,
533 only a shallow copy will be made.
538 Using the copy or the original with overloaded math is okay, e.g. the
542 print $x + 1, " ", $y,"\n"; # prints 10 9
544 but calling any method that modifies the number directly will result in
545 B<both> the original and the copy being destroyed:
548 print $x->badd(1), " ", $y,"\n"; # prints 10 10
551 print $x->binc(1), " ", $y,"\n"; # prints 10 10
554 print $x->bmul(2), " ", $y,"\n"; # prints 18 18
556 Using methods that do not modify, but testthe contents works:
559 $z = 9 if $x->is_zero(); # works fine
561 See the documentation about the copy constructor and C<=> in overload, as
562 well as the documentation in BigInt for further details.
570 This method only works on Perl v5.9.4 or later.
574 C<bigint> overrides these routines with versions that can also handle
575 big integer values. Under Perl prior to version v5.9.4, however, this
576 will not happen unless you specifically ask for it with the two
577 import tags "hex" and "oct" - and then it will be global and cannot be
578 disabled inside a scope with "no bigint":
580 use bigint qw/hex oct/;
582 print hex("0x1234567890123456");
585 print hex("0x1234567890123456");
588 The second call to hex() will warn about a non-portable constant.
594 # will warn only under Perl older than v5.9.4
595 print hex("0x1234567890123456");
601 C<bigint> is just a thin wrapper around various modules of the Math::BigInt
602 family. Think of it as the head of the family, who runs the shop, and orders
603 the others to do the work.
605 The following modules are currently used by bigint:
607 Math::BigInt::Lite (for speed, and only if it is loadable)
612 Some cool command line examples to impress the Python crowd ;) You might want
613 to compare them to the results under -Mbignum or -Mbigrat:
615 perl -Mbigint -le 'print sqrt(33)'
616 perl -Mbigint -le 'print 2*255'
617 perl -Mbigint -le 'print 4.5+2*255'
618 perl -Mbigint -le 'print 3/7 + 5/7 + 8/3'
619 perl -Mbigint -le 'print 123->is_odd()'
620 perl -Mbigint -le 'print log(2)'
621 perl -Mbigint -le 'print 2 ** 0.5'
622 perl -Mbigint=a,65 -le 'print 2 ** 0.2'
623 perl -Mbignum=a,65,l,GMP -le 'print 7 ** 7777'
627 This program is free software; you may redistribute it and/or modify it under
628 the same terms as Perl itself.
632 Especially L<bigrat> as in C<perl -Mbigrat -le 'print 1/3+1/4'> and
633 L<bignum> as in C<perl -Mbignum -le 'print sqrt(2)'>.
635 L<Math::BigInt>, L<Math::BigRat> and L<Math::Big> as well
636 as L<Math::BigInt::BitVect>, L<Math::BigInt::Pari> and L<Math::BigInt::GMP>.
640 (C) by Tels L<http://bloodgate.com/> in early 2002 - 2007.