How to approximately equal two numbers in PHP with this PHP function / method.

title tags
approximatelyEqual
math,beginner

Checks if two numbers are approximately equal to each other.

  • Use abs() to compare the absolute difference of the two values to $epsilon.
  • Omit the third parameter, $epsilon, to use a default value of 0.001.
function approximatelyEqual($number1, $number2, $epsilon = 0.001)
{
  return abs($number1 - $number2) < $epsilon;
}
approximatelyEqual(10.0, 10.00001); // true

approximatelyEqual(10.0, 10.01); // false