public SDVariable mmul(String name, SDVariable x, SDVariable y) {
    SDValidation.validateNumerical("mmul", "x", x);
    SDValidation.validateNumerical("mmul", "y", y);
    SDVariable out =  new org.nd4j.linalg.api.ops.impl.reduce.Mmul(sd,x, y, false, false, false).outputVariable();
    return sd.updateVariableNameAndReference(out, name);