Beware that negative zero does not compare equal to positive zero.
(PHP 4, PHP 5, PHP 7, PHP 8)
bccomp — 2 つの任意精度数値を比較する
num1左オペランドを表す文字列。
num2右オペランドを表す文字列。
scalenull, it will default to the default scale set with bcscale(),
or fallback to the value of the
bcmath.scale INI directive.
ふたつのオペランドが等しければ 0、
num1 が num2
より大きければ戻り値は 1、小さければ -1 を返します。
This function throws a ValueError in the following cases:
num1 or num2
is not a well-formed BCMath numeric string.
scale is outside the valid range.
| バージョン | 説明 |
|---|---|
| 8.0.0 |
scale は、nullable になりました。
|
例1 bccomp() の例
<?php
echo bccomp('1', '2') . "\n"; // -1
echo bccomp('1.00001', '1', 3); // 0
echo bccomp('1.00001', '1', 5); // 1
?>BEWARE! left and right operand is string!! so number in E-notation like 9.012E-6 need to be converted with sprintf('%F') to stringIf you want to compare 2 decimals for equality, bccomp does not works as expected:
bccomp("1.000000000000000","0.999999999999999",2)
returns 1
Instead, use
bcsub("1.000000000000000","0.999999999999999",2) == 0Improvement of functions bcmax() and bcmin() originaly written by frank at booksku dot com
<?php
function bcmax() {
$args = func_get_args();
if (count($args)==0) return false;
$max = $args[0];
foreach($args as $value) {
if (bccomp($value, $max)==1) {
$max = $value;
}
}
return $max;
}
function bcmin() {
$args = func_get_args();
if (count($args)==0) return false;
$min = $args[0];
foreach($args as $value) {
if (bccomp($min, $value)==1) {
$min = $value;
}
}
return $min;
}
?>