gmp_cmp
(PHP 4 >= 4.0.4, PHP 5, PHP 7, PHP 8)
gmp_cmp — 数を比較する
戻り値
a > b の場合に正の値、a = b
の場合にゼロ、a < b の場合に負の値を返します。
例
例1 gmp_cmp() の例
<?php
$cmp1 = gmp_cmp("1234", "1000"); // より大きい
$cmp2 = gmp_cmp("1000", "1234"); // より小さい
$cmp3 = gmp_cmp("1234", "1234"); // 等しい
echo "$cmp1 $cmp2 $cmp3\n";
?>上の例の出力は以下となります。
1 -1 0
＋add a note
User Contributed Notes 1 note
russell dot harper at springboardnetworks dot com ¶
14 years ago
I've encountered a memory leak in gmp_cmp if a literal string is used as the second value inside of loops. A workaround is to initialize first, then use the variable. I wasn't able to generate a minimum code sample, it's something more complicated, but I was able to fix it as follows:
<?php
$x = gmp_init(strval(mt_rand()));
// Depending on surrounding code, may have leaks
while (true)
{
if (!gmp_cmp($x, '1'))
print 'one'."\n";
}
// Usually doesn't have leaks
$one = gmp_init('1');
while (true)
{
if (!gmp_cmp($x, $one))
print 'one'."\n";
}
?>
↑ and ↓ to navigate •
Enter to select •
Esc to close
Press Enter without
selection to search using Google