# Pastebin mEqe5r3r
if ((padW != 0 || padH != 0) &&
          (gradientTemp.n_rows < output.n_rows &&
          gradientTemp.n_cols < output.n_cols))
      {
        gradientTemp.slice(outMapIdx) += output.submat(padW, padH,
            padW + gradientTemp.n_rows - 1,
            padH + gradientTemp.n_cols - 1);
      }
      else
      {
        gradientTemp.slice(outMapIdx) += output;
      }