|Perl Language Reference Manual|
by Larry Wall and others
Paperback (6"x9"), 724 pages
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7.39 Bigger Numbers
The standard Math::BigInt and Math::BigFloat modules provide variable-precision arithmetic and overloaded operators, although they're currently pretty slow. At the cost of some space and considerable speed, they avoid the normal pitfalls associated with limited-precision representations.
use Math::BigInt; $x = Math::BigInt->new('123456789123456789'); print $x * $x; # prints +15241578780673678515622620750190521
There are several modules that let you calculate with (bound only by memory and cpu-time) unlimited or fixed precision. There are also some non-standard modules that provide faster implementations via external C libraries.
Here is a short, but incomplete summary:
Math::Fraction big, unlimited fractions like 9973 / 12967 Math::String treat string sequences like numbers Math::FixedPrecision calculate with a fixed precision Math::Currency for currency calculations Bit::Vector manipulate bit vectors fast (uses C) Math::BigIntFast Bit::Vector wrapper for big numbers Math::Pari provides access to the Pari C library Math::BigInteger uses an external C library Math::Cephes uses external Cephes C library (no big numbers) Math::Cephes::Fraction fractions via the Cephes library Math::GMP another one using an external C library
|ISBN 9781906966027||Perl Language Reference Manual||See the print edition|