Function: minus(gradient[0](mean(numbers("xxr") if numbers("yxx") > numbers('xry') else sum(numbers("yxx"), numbers('xry')), sum(numbers("yxx"), numbers('xry')))), mean(sum(numbers("yxx"), numbers('xry')) if numbers("xxr") > numbers("yxx") else numbers('xry'), sum(numbers("yxx"), numbers('xry'))))
