Function: mod(minus(numbers("per"), numbers('yyx')) if numbers('yyx') if minus(numbers("per"), numbers('yyx')) > numbers("per") else gradient[2](minus(numbers("per"), numbers('yyx'))) > gradient[2](minus(numbers("per"), numbers('yyx'))) else numbers("per"), numbers("per") if gradient[2](minus(numbers("per"), numbers('yyx'))) > numbers('yyx') else minus(numbers("per"), numbers('yyx')))
