code: public SDVariable clipByNorm(SDVariable x, double clipValue, int... dimensions) {
          return clipByNorm(null, x, clipValue, dimensions);
      }
docs: Clipping by L2 norm, optionally along dimension(s)<br>
  if l2Norm(x,dimension) < clipValue, then input is returned unmodifed<br>
  Otherwise, out[i] = in[i] * clipValue / l2Norm(in, dimensions) where each value is clipped according
  to the corresponding l2Norm along the specified dimensions
  
  @param x          Input variable
  @param clipValue  Clipping value (maximum l2 norm)
  @param dimensions If not specified, all dimensions are used
  @return Output variable