code: public SDVariable cross(String name, SDVariable a, SDVariable b) {
          validateNumerical("cross", a, b);
          SDVariable ret = f().cross(a, b);
          return updateVariableNameAndReference(ret, name);
      }
docs: Returns the pair-wise cross product of equal size arrays a and b: a x b = ||a||x||b|| sin(theta).
  Can take rank 1 or above inputs (of equal shapes), but note that the last dimension must have dimension 3
  
  @param a First input
  @param b Second input
  @return Element-wise cross product