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gmp_init

(PHP 4 >= 4.0.4, PHP 5, PHP 7, PHP 8)

gmp_init — Create GMP number

Description

gmp_init(int|string $num, int $base = 0): GMP

Creates a GMP number from an integer or string.

Parameters

num
An integer or a string. The string representation can be decimal, hexadecimal, octal, or binary.
base
The base to use for converting a string representation. An explicit base can be between 2 and 62. For bases up to 36, case is ignored; upper-case and lower-case letters have the same value. For bases 37 to 62, upper-case letter represent the values 10 to 35 and lower-case letter represent the values 36 to 61. If base is 0 then the actual base is determined from the leading characters of num. If the first two characters are 0x or 0X, the string is interpreted as a hexadecimal integer. If the first two characters are 0b or 0B, the string is interpreted as a binary integer. If the first two characters are 0o or 0o, the string is interpreted as an octal integer. Moreover, if the first character is 0 the string is also interpreted as an octal integer. In all other cases, the string is interpreted as a decimal integer.

Return Values

A GMP object.

Changelog

Version Description
8.1.0 Support for explicit octal prefixes 0o and 0o has been added for num strings. Interpretation of such prefixes when base is 0 has also been added.

Examples

Example #1 Creating GMP number

<?php
$a = gmp_init(123456);
$b = gmp_init("0xFFFFDEBACDFEDF7200");
?>

Notes

Note:

It is not necessary to call this function in order to use integers or strings in place of GMP numbers in GMP functions (such as with gmp_add()). Function arguments are automatically converted to GMP numbers, if such conversion is possible and needed, using the same rules as gmp_init().

See Also

© 1997–2025 The PHP Documentation Group
Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.gmp-init.php