PHP5中文手册·Sign of number -- 追寻梦想＞编程乐园＞PHP 编程

int gmp_sign ( resource $a )

Checks the sign of a number.

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.

Returns 1 if a is positive, -1 if a is negative, and 0 if a is zero.

Example#1 gmp_sign() example


<?php
// positive
echo gmp_sign("500") . "\n";

// negative
echo gmp_sign("-500") . "\n";

// zero
echo gmp_sign("0") . "\n";
?>

上例将输出：

1
-1
0


	PHP5中文手册 gmp_setbit gmp_sqrt GMP PHP Manual gmp_sign (PHP 4 >= 4.0.4, PHP 5) gmp_sign — Sign of number 说明 int gmp_sign ( resource `$a` ) Checks the sign of a number. 参数 `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. 返回值 Returns 1 if `a` is positive, -1 if `a` is negative, and 0 if `a` is zero. 范例 Example#1 gmp_sign() example `<?php // positive echo gmp_sign("500") . "\n"; // negative echo gmp_sign("-500") . "\n"; // zero echo gmp_sign("0") . "\n"; ?>` 上例将输出： 1 -1 0 gmp_setbit gmp_sqrt GMP PHP Manual