Function: gradient[0](numbers('xry') if numbers('epe') > numbers("per") else numbers("per") if numbers('epe') > minus(numbers("per") if numbers("per") > numbers('epe') else numbers('xry'), numbers('epe')) else numbers("per") if minus(numbers("per") if numbers("per") > numbers('xry') else numbers('epe'), numbers('epe')) > numbers('epe') else numbers("per") if numbers('epe') > numbers('xry') else numbers("per"))
