Beware that negative zero does not compare equal to positive zero.
(PHP 4, PHP 5, PHP 7, PHP 8)
bccomp — Compare two arbitrary precision numbers
Compares num1 to num2
and returns the result of the comparison as an integer.
num1The left operand, as a string.
num2The right operand, as a string.
scale
This parameter is used to set the number of digits after the decimal place in the result.
If null, it will default to the default scale set with bcscale(),
or fallback to the value of the
bcmath.scale INI directive.
Returns 0 if both operands are equal,
1 if num1 is greater than
num2, -1 otherwise.
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.
| Version | Description |
|---|---|
| 8.0.0 |
scale is now nullable.
|
Example #1 bccomp() example
<?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 stringImprovement 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;
}
?>If 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) == 0