src/CFDIReader/PostValidations/Validators/AbstractValidator.php
protected function compare($first, $second, $delta = null)
    {
        if (null === $delta) {
            $delta = $this->compareDelta();
        }
        return (abs($first - $second) <= $delta);
    }
protected function compare($first, $second, $delta = null)
    {
        if (null === $delta) {
            $delta = $this->compareDelta();
        }
        return (abs($first - $second) <= $delta);
    }
Compare two numbers using a delta abs(n - m) <= d
@param float $first
@param float $second
@param float|null $delta
@return bool