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Math::BigInt::Calc - pure Perl module to support Math::BigInt


# to use it with Math::BigInt
use Math::BigInt lib => 'Calc';

# to use it with Math::BigFloat
use Math::BigFloat lib => 'Calc';

# to use it with Math::BigRat
use Math::BigRat lib => 'Calc';

# explicitly set base length and whether to "use integer"
use Math::BigInt::Calc base_len => 4, use_int => 1;
use Math::BigInt lib => 'Calc';


Math::BigInt::Calc inherits from Math::BigInt::Lib.

In this library, the numbers are represented interenally in base B = 10**N, where N is the largest possible integer that does not cause overflow in the intermediate computations. The base B elements are stored in an array, with the least significant element stored in array element zero. There are no leading zero elements, except a single zero element when the number is zero. For instance, if B = 10000, the number 1234567890 is represented internally as [7890, 3456, 12].


When the module is loaded, it computes the maximum exponent, i.e., power of 10, that can be used with and without "use integer" in the computations. The default is to use this maximum exponent. If the combination of the 'base_len' value and the 'use_int' value exceeds the maximum value, an error is thrown.


The base length can be specified explicitly with the 'base_len' option. The value must be a positive integer.

use Math::BigInt::Calc base_len => 4;  # use 10000 as internal base

This option is used to specify whether "use integer" should be used in the internal computations. The value is interpreted as a boolean value, so use 0 or "" for false and anything else for true. If the 'base_len' is not specified together with 'use_int', the current value for the base length is used.

use Math::BigInt::Calc use_int => 1;   # use "use integer" internally


This overview constains only the methods that are specific to Math::BigInt::Calc. For the other methods, see Math::BigInt::Lib.


Specify the desired base length and whether to enable "use integer" in the computations.

Math::BigInt::Calc -> _base_len($base_len, $use_int);

Note that it is better to specify the base length and whether to use integers as options when the module is loaded, for example like this

use Math::BigInt::Calc base_len => 6, use_int => 1;


Math::BigInt::Lib for a description of the API.

Alternative libraries Math::BigInt::FastCalc, Math::BigInt::GMP, Math::BigInt::Pari, Math::BigInt::GMPz, and Math::BigInt::BitVect.

Some of the modules that use these libraries Math::BigInt, Math::BigFloat, and Math::BigRat.