Method Backward_gpu

include/caffe/layer.hpp:334–339

* @brief Using the GPU device, compute the gradients for any parameters and * for the bottom blobs if propagate_down is true. * Fall back to Backward_cpu() if unavailable. */

   *        Fall back to Backward_cpu() if unavailable.
   */
  virtual void Backward_gpu(const vector<Blob<Dtype>*>& top,
      const vector<bool>& propagate_down,
      const vector<Blob<Dtype>*>& bottom) {
    // LOG(WARNING) << "Using CPU code as backup.";
    Backward_cpu(top, propagate_down, bottom);
  }

  /**
   * Called by the parent Layer's SetUp to check that the number of bottom