1Math::GMP(3)          User Contributed Perl Documentation         Math::GMP(3)
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NAME

6       Math::GMP - High speed arbitrary size integer math
7

SYNOPSIS

9         use Math::GMP;
10         my $n = new Math::GMP 2;
11
12         $n = $n ** (256*1024);
13         $n = $n - 1;
14         print "n is now $n\n";
15

DESCRIPTION

17       Math::GMP was designed to be a drop-in replacement both for
18       Math::BigInt and for regular integer arithmetic.  Unlike BigInt,
19       though, Math::GMP uses the GNU gmp library for all of its calculations,
20       as opposed to straight Perl functions.  This can result in speed
21       improvements.
22
23       The downside is that this module requires a C compiler to install -- a
24       small tradeoff in most cases. Also, this module is not 100% compatible
25       to Math::BigInt.
26
27       A Math::GMP object can be used just as a normal numeric scalar would be
28       -- the module overloads most of the normal arithmetic operators to
29       provide as seamless an interface as possible. However, if you need a
30       perfect interface, you can do the following:
31
32         use Math::GMP qw(:constant);
33
34         $n = 2 ** (256 * 1024);
35         print "n is $n\n";
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37       This would fail without the ':constant' since Perl would use normal
38       doubles to compute the 250,000 bit number, and thereby overflow it into
39       meaninglessness (smaller exponents yield less accurate data due to
40       floating point rounding).
41

METHODS

43       Although the non-overload interface is not complete, the following
44       functions do exist:
45
46   new
47         $x = Math::GMP->new(123);
48
49       Creates a new Math::GMP object from the passed string or scalar.
50
51         $x = Math::GMP->new('abcd', 36);
52
53       Creates a new Math::GMP object from the first parameter which should be
54       represented in the base specified by the second parameter.
55
56   bfac
57         $x = Math::GMP->new(5);
58         $x->bfac();      # 1*2*3*4*5 = 120
59
60       Calculates the factorial of $x and modifies $x to contain the result.
61
62   band
63         $x = Math::GMP->new(6);
64         $x->band(3);      # 0b110 & 0b11 = 1
65
66       Calculates the bit-wise AND of it's two arguments and modifies the
67       first argument.
68
69   bxor
70         $x = Math::GMP->new(6);
71         $x->bxor(3);      # 0b110 & 0b11 = 0b101
72
73       Calculates the bit-wise XOR of it's two arguments and modifies the
74       first argument.
75
76   bior
77         $x = Math::GMP->new(6);
78         $x->bior(3);      # 0b110 & 0b11 = 0b111
79
80       Calculates the bit-wise OR of it's two arguments and modifies the first
81       argument.
82
83   bgcd
84         $x = Math::GMP->new(6);
85         $x->bgcd(4);      # 6 / 2 = 2, 4 / 2 = 2 => 2
86
87       Calculates the Greatest Common Divisior of it's two arguments and
88       returns the result.
89
90   legendre
91   jacobi
92   fibonacci
93         $x = Math::GMP->fibonacci(16);
94
95       Calculates the n'th number in the Fibonacci sequence.
96
97   probab_prime
98         $x = Math::GMP->new(7);
99         $x->probab_prime(10);
100
101       Probabilistically Determines if the number is a prime. Argument is the
102       number of checks to perform. Returns 0 if the number is definitely not
103       a prime, 1 if it may be, and 2 if it is definitely is a prime.
104

BUGS

106       As of version 1.0, Math::GMP is mostly compatible with the old
107       Math::BigInt version. It is not a full replacement for the rewritten
108       Math::BigInt versions, though. See the SEE ALSO section on how to
109       achieve to use Math::GMP and retain full compatibility to Math::BigInt.
110
111       There are some slight incompatibilities, such as output of positive
112       numbers not being prefixed by a '+' sign.  This is intentional.
113
114       There are also some things missing, and not everything might work as
115       expected.
116

SEE ALSO

118       Math::BigInt has a new interface to use a different library than the
119       default pure Perl implementation. You can use, for instance, Math::GMP
120       with it:
121
122         use Math::BigInt lib => 'GMP';
123
124       If Math::GMP is not installed, it will fall back to it's own Perl
125       implementation.
126
127       See Math::BigInt and Math::BigInt::GMP or Math::BigInt::Pari or
128       Math::BigInt::BitVect.
129

AUTHOR

131       Chip Turner <chip@redhat.com>, based on the old Math::BigInt by Mark
132       Biggar and Ilya Zakharevich.  Further extensive work provided by Tels
133       <tels@bloodgate.com>.
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137perl v5.12.2                      2009-09-17                      Math::GMP(3)