Math::GMP(3) User Contributed Perl Documentation Math::GMP(3)NAMEMath::GMP - High speed arbitrary size integer math
SYNOPSIS
use Math::GMP;
my $n = new Math::GMP 2;
$n = $n ** (256*1024);
$n = $n - 1;
print "n is now $n\n";
DESCRIPTIONMath::GMP was designed to be a drop-in replacement both for
Math::BigInt and for regular integer arithmetic. Unlike BigInt,
though, Math::GMP uses the GNU gmp library for all of its calculations,
as opposed to straight Perl functions. This can result in speed
improvements.
The downside is that this module requires a C compiler to install -- a
small tradeoff in most cases. Also, this module is not 100% compatible
to Math::BigInt.
A Math::GMP object can be used just as a normal numeric scalar would be
-- the module overloads most of the normal arithmetic operators to
provide as seamless an interface as possible. However, if you need a
perfect interface, you can do the following:
use Math::GMP qw(:constant);
$n = 2 ** (256 * 1024);
print "n is $n\n";
This would fail without the ':constant' since Perl would use normal
doubles to compute the 250,000 bit number, and thereby overflow it into
meaninglessness (smaller exponents yield less accurate data due to
floating point rounding).
METHODS
Although the non-overload interface is not complete, the following
functions do exist:
new
$x = Math::GMP->new(123);
Creates a new Math::GMP object from the passed string or scalar.
$x = Math::GMP->new('abcd', 36);
Creates a new Math::GMP object from the first parameter which should be
represented in the base specified by the second parameter.
bfac
$x = Math::GMP->new(5);
$x->bfac(); # 1*2*3*4*5 = 120
Calculates the factorial of $x and modifies $x to contain the result.
band
$x = Math::GMP->new(6);
$x->band(3); # 0b110 & 0b11 = 1
Calculates the bit-wise AND of it's two arguments and modifies the
first argument.
bxor
$x = Math::GMP->new(6);
$x->bxor(3); # 0b110 & 0b11 = 0b101
Calculates the bit-wise XOR of it's two arguments and modifies the
first argument.
bior
$x = Math::GMP->new(6);
$x->bior(3); # 0b110 & 0b11 = 0b111
Calculates the bit-wise OR of it's two arguments and modifies the first
argument.
bgcd
$x = Math::GMP->new(6);
$x->bgcd(4); # 6 / 2 = 2, 4 / 2 = 2 => 2
Calculates the Greatest Common Divisior of it's two arguments and
returns the result.
legendre
jacobi
fibonacci
$x = Math::GMP->fibonacci(16);
Calculates the n'th number in the Fibonacci sequence.
probab_prime
$x = Math::GMP->new(7);
$x->probab_prime(10);
Probabilistically Determines if the number is a prime. Argument is the
number of checks to perform. Returns 0 if the number is definitely not
a prime, 1 if it may be, and 2 if it is definitely is a prime.
BUGS
As of version 1.0, Math::GMP is mostly compatible with the old
Math::BigInt version. It is not a full replacement for the rewritten
Math::BigInt versions, though. See the SEE ALSO section on how to
achieve to use Math::GMP and retain full compatibility to Math::BigInt.
There are some slight incompatibilities, such as output of positive
numbers not being prefixed by a '+' sign. This is intentional.
There are also some things missing, and not everything might work as
expected.
SEE ALSO
Math::BigInt has a new interface to use a different library than the
default pure Perl implementation. You can use, for instance, Math::GMP
with it:
use Math::BigInt lib => 'GMP';
If Math::GMP is not installed, it will fall back to it's own Perl
implementation.
See Math::BigInt and Math::BigInt::GMP or Math::BigInt::Pari or
Math::BigInt::BitVect.
AUTHOR
Chip Turner <chip@redhat.com>, based on the old Math::BigInt by Mark
Biggar and Ilya Zakharevich. Further extensive work provided by Tels
<tels@bloodgate.com>.
perl v5.14.1 2009-09-17 Math::GMP(3)
