PHP | gmp_neg() Function Last Updated : 11 Jul, 2025 Comments Improve Suggest changes Like Article Like Report The gmp_neg() function is an in-built function in PHP which returns the negative of a GMP number (GNU Multiple Precision). Syntax : gmp_neg( $num ) Parameters : The function accepts only one mandatory parameter $num which can be either a GMP number resource in PHP 5.5 or a GMP object in PHP version 5.6 and later, or numeric strings can be passed to the function provided that it is possible to convert those strings to numbers. Return Values : This function returns a GMP number (in PHP 5.5 and earlier) or a GMP object (in PHP 5.6 and later) which is negative of the value of $num. Examples : Input : $num = 255 Output : -255 Input : $num = 128 Output : -128 Below programs will illustrate the gmp_neg() function : Program 1: php <?php //PHP program to illustrate //gmp_neg() function $num = gmp_init("255"); $num1 = gmp_neg($num); echo gmp_strval($num1); ?> Output: -255 Program 2: php <?php //PHP program to illustrate //gmp_neg() function $num = gmp_init("314567128"); $num1 = gmp_neg($num); echo gmp_strval($num1); ?> Output: -314567128 Reference : https://www.php.net/manual/en/function.gmp-neg.php Comment R RICHIK BHATTACHARJEE Follow 0 Improve R RICHIK BHATTACHARJEE Follow 0 Improve Article Tags : Misc Web Technologies PHP PHP-gmp Explore PHP Tutorial 8 min read BasicsPHP Syntax 4 min read PHP Variables 5 min read PHP | Functions 8 min read PHP Loops 4 min read ArrayPHP Arrays 5 min read PHP Associative Arrays 4 min read Multidimensional arrays in PHP 5 min read Sorting Arrays in PHP 4 min read OOPs & InterfacesPHP Classes 2 min read PHP | Constructors and Destructors 5 min read PHP Access Modifiers 4 min read Multiple Inheritance in PHP 4 min read MySQL DatabasePHP | MySQL Database Introduction 4 min read PHP Database connection 2 min read PHP | MySQL ( Creating Database ) 3 min read PHP | MySQL ( Creating Table ) 3 min read PHP AdvancePHP Superglobals 6 min read PHP | Regular Expressions 12 min read PHP Form Handling 4 min read PHP File Handling 4 min read PHP | Uploading File 3 min read PHP Cookies 9 min read PHP | Sessions 7 min read Like