# gmp_invert

(PHP 4 >= 4.0.4, PHP 5)

gmp_invert — Inverse by modulo

### Description

resource gmp_invert ( resource `$a` , resource `$b` )

Computes the inverse of `a` modulo `b` .

### Parameters

`a`

  It can be either a GMP number resource, or a numeric string given that it is possible to convert the latter to a number.

`b`

  It can be either a GMP number resource, or a numeric string given that it is possible to convert the latter to a number.

### Return Values

A GMP number on success or `FALSE` if an inverse does not exist.

### Examples

Example#1 gmp_invert() example

`<?php
echo gmp_invert("5", "10"); // no inverse, outputs nothing, result is FALSE
$invert = gmp_invert("5", "11");
echo gmp_strval($invert) . "\n";
?>`

The above example will output:

    9