(PHP 4 >= 4.0.4, PHP 5, PHP 7, PHP 8)
gmp_clrbit — Clear bit
Clears (sets to 0) bit index in
num. The index starts at 0.
numGMP 对象或 int ，或数字string。
indexThe index of the bit to clear. Index 0 represents the least significant bit.
GMP 对象。
Example #1 gmp_clrbit() example
<?php
$a = gmp_init("0xff");
gmp_clrbit($a, 0); // index starts at 0, least significant bit
echo gmp_strval($a) . "\n";
?>
以上例程会输出：
254
Note:
Unlike most of the other GMP functions, gmp_clrbit() must be called with a GMP object that already exists (using gmp_init() for example). One will not be automatically created.