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    bccomp

    (PHP 4, PHP 5, PHP 7, PHP 8)

    bccomp — Compare two arbitrary precision numbers

    Description

    function bccomp(string $num1, string $num2, ?int $scale = null): int

    Compares num1 to num2 and returns the result of the comparison as an integer.

    Parameters

    num1

    The left operand, as a string.

    num2

    The 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.

    Return Values

    Returns 0 if both operands are equal, 1 if num1 is greater than num2, -1 otherwise.

    Errors/Exceptions

    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.

    Changelog

    Version Description
    8.0.0 scale is now nullable.

    Examples

    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

?>

    See Also

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    User Contributed Notes 4 notes

    up
    26
    Robert Lozyniak
    16 years ago
    Beware that negative zero does not compare equal to positive zero.
    up
    16
    aaugrin at gmail dot com
    8 years ago
    BEWARE! left and right operand is string!! so number in E-notation like 9.012E-6  need to be converted with sprintf('%F') to string
    up
    -2
    m dot kaczanowski at alianet dot pl
    17 years ago
    Improvement 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;
}
?>
    up
    -1
    mm at mobelt dot com
    1 year ago
    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
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