kmath/kmath-torch/ctorch/include/utils.hh
2021-01-16 19:19:03 +00:00

141 lines
4.4 KiB
C++

#include <torch/torch.h>
#include "ctorch.h"
namespace ctorch
{
template <typename Dtype>
inline c10::ScalarType dtype()
{
return torch::kFloat64;
}
template <>
inline c10::ScalarType dtype<float>()
{
return torch::kFloat32;
}
template <>
inline c10::ScalarType dtype<long>()
{
return torch::kInt64;
}
template <>
inline c10::ScalarType dtype<int>()
{
return torch::kInt32;
}
inline torch::Tensor &cast(const TorchTensorHandle &tensor_handle)
{
return *static_cast<torch::Tensor *>(tensor_handle);
}
inline char *tensor_to_char(const torch::Tensor &tensor)
{
std::stringstream bufrep;
bufrep << tensor;
auto rep = bufrep.str();
char *crep = (char *)malloc(rep.length() + 1);
std::strcpy(crep, rep.c_str());
return crep;
}
inline int device_to_int(const torch::Tensor &tensor)
{
return (tensor.device().type() == torch::kCPU) ? 0 : 1 + tensor.device().index();
}
inline torch::Device int_to_device(int device_int)
{
return (device_int == 0) ? torch::kCPU : torch::Device(torch::kCUDA, device_int - 1);
}
inline std::vector<int64_t> to_vec_int(int *arr, int arr_size)
{
auto vec = std::vector<int64_t>(arr_size);
vec.assign(arr, arr + arr_size);
return vec;
}
inline std::vector<at::indexing::TensorIndex> to_index(int *arr, int arr_size)
{
std::vector<at::indexing::TensorIndex> index;
for (int i = 0; i < arr_size; i++)
{
index.emplace_back(arr[i]);
}
return index;
}
template <typename Dtype>
inline torch::Tensor from_blob(Dtype *data, std::vector<int64_t> shape, torch::Device device, bool copy)
{
return torch::from_blob(data, shape, dtype<Dtype>()).to(torch::TensorOptions().layout(torch::kStrided).device(device), false, copy);
}
template <typename NumType>
inline NumType get(const TorchTensorHandle &tensor_handle, int *index)
{
auto ten = ctorch::cast(tensor_handle);
return ten.index(to_index(index, ten.dim())).item<NumType>();
}
template <typename NumType>
inline void set(TorchTensorHandle &tensor_handle, int *index, NumType value)
{
auto ten = ctorch::cast(tensor_handle);
ten.index(to_index(index, ten.dim())) = value;
}
template <typename Dtype>
inline torch::Tensor randn(std::vector<int64_t> shape, torch::Device device)
{
return torch::randn(shape, torch::TensorOptions().dtype(dtype<Dtype>()).layout(torch::kStrided).device(device));
}
template <typename Dtype>
inline torch::Tensor rand(std::vector<int64_t> shape, torch::Device device)
{
return torch::rand(shape, torch::TensorOptions().dtype(dtype<Dtype>()).layout(torch::kStrided).device(device));
}
template <typename Dtype>
inline torch::Tensor randint(long low, long high, std::vector<int64_t> shape, torch::Device device)
{
return torch::randint(low, high, shape, torch::TensorOptions().dtype(dtype<Dtype>()).layout(torch::kStrided).device(device));
}
template <typename Dtype>
inline torch::Tensor full(Dtype value, std::vector<int64_t> shape, torch::Device device)
{
return torch::full(shape, value, torch::TensorOptions().dtype(dtype<Dtype>()).layout(torch::kStrided).device(device));
}
inline torch::Tensor hessian(const torch::Tensor &value, const torch::Tensor &variable)
{
auto nelem = variable.numel();
auto hess = value.new_zeros({nelem, nelem});
auto grad = torch::autograd::grad({value}, {variable}, {}, torch::nullopt, true)[0].view(nelem);
int i = 0;
for (int j = 0; j < nelem; j++)
{
auto row = grad[j].requires_grad()
? torch::autograd::grad({grad[i]}, {variable}, {}, true, true, true)[0].view(nelem).slice(0, j, nelem)
: grad[j].new_zeros(nelem - j);
hess[i].slice(0, i, nelem).add_(row.type_as(hess));
i++;
}
auto ndim = variable.dim();
auto sizes = variable.sizes().data();
auto shape = std::vector<int64_t>(ndim);
shape.assign(sizes, sizes + ndim);
shape.reserve(2 * ndim);
std::copy_n(shape.begin(), ndim, std::back_inserter(shape));
return (hess + torch::triu(hess, 1).t()).view(shape);
}
} // namespace ctorch