text: #ifndef CAFFE2_OPERATORS_ORDER_SWITCH_OPS_H_
  #define CAFFE2_OPERATORS_ORDER_SWITCH_OPS_H_
  
  #include <vector>
  
  #include "caffe2/core/operator.h"
  #include "caffe2/utils/math.h"
  
  namespace caffe2 {
  
  // Note(Yangqing): I think it is possible to do a more general swapaxes operator
  // but I am a little afraid of going down that general path. Only implementing
  // the two actually needed ones here.
  
  template <typename T, class Context>
  class NHWC2NCHWOp final : public Operator<Context> {
   public:
    USE_OPERATOR_CONTEXT_FUNCTIONS;
  
    USE_SIMPLE_CTOR_DTOR(NHWC2NCHWOp);
  
    bool RunOnDevice() override {
      const auto& X = Input(0);
  
      const int ndim = X.dim();
      CAFFE_ENFORCE_GE(ndim, 3);
      const int N = X.dim32(0);
      const int C = X.dim32(ndim - 1);
      std::vector<int64_t> Y_dims(ndim);
      Y_dims[0] = N;
      Y_dims[1] = C;
      int HxW = 1;
      for (const auto i : c10::irange(2, ndim)) {
        Y_dims[i] = X.dim32(i - 1);
        HxW *= Y_dims[i];
      }
      auto* Y = Output(0, Y_dims, at::dtype<T>());
      if (X.numel() <= 0) {
        return true;
      }
      math::NHWC2NCHW<T, Context>(
          N,
          C,
          HxW,
          X.template data<T>(),
          Y->template mutable_data<T>(),
          &context_);
      return true;
    }
  };
  
  template <typename T, class Context>
  class NCHW2NHWCOp final : public Operator<Context> {
   public:
    USE_OPERATOR_CONTEXT_FUNCTIONS;
  
    USE_SIMPLE_CTOR_DTOR(NCHW2NHWCOp);
  
    bool RunOnDevice() override {
      const auto& X = Input(0);
  
      const int ndim = X.dim();
      CAFFE_ENFORCE_GE(ndim, 3);
      const int N = X.dim32(0);
      const int C = X.dim32(1);
      std::vector<int64_t> Y_dims(ndim);
      Y_dims[0] = N;
      Y_dims[ndim - 1] = C;
      int HxW = 1;
      for (int i = 1; i < ndim - 1; ++i) {
        Y_dims[i] = X.dim32(i + 1);
        HxW *= Y_dims[i];
      }
      auto* Y = Output(0, Y_dims, at::dtype<T>());
      if (X.numel() <= 0) {
        return true;
      }
      math::NCHW2NHWC<T, Context>(
          N,
          C,
          HxW,
          X.template data<T>(),
          Y->template mutable_data<T>(),
          &context_);
      return true;
    }
  };
  
  } // namespace caffe2
  
  #endif // CAFFE2_OPERATORS_ORDER_SWITCH_OPS_H_
  