fann_set_train_error_function Sets the error function used during training &reftitle.description; boolfann_set_train_error_function resourceann interror_function Sets the error function used during training. The error functions are described further in error functions constants. &reftitle.parameters; ann &fann.ann.description; error_function The error function constant &reftitle.returnvalues; &fann.return.bool; &reftitle.seealso; fann_get_train_error_function