Rate this Page

Archives#

Archives provide a lower-level interface for serialization, allowing you to save multiple values to a single file with named keys.

OutputArchive#

class OutputArchive#

Public Functions

explicit OutputArchive(std::shared_ptr<jit::CompilationUnit> cu)#
inline explicit OutputArchive()#
OutputArchive(OutputArchive&&) = default#
OutputArchive &operator=(OutputArchive&&) = default#
OutputArchive(OutputArchive&) = delete#
OutputArchive &operator=(OutputArchive&) = delete#
inline std::shared_ptr<jit::CompilationUnit> compilation_unit() const#
void write(const std::string &key, const c10::IValue &ivalue)#

Writes an IValue to the OutputArchive.

void write(const std::string &key, const Tensor &tensor, bool is_buffer = false)#

Writes a (key, tensor) pair to the OutputArchive, and marks it as being or not being a buffer (non-differentiable tensor).

void write(const std::string &key, OutputArchive &nested_archive)#

Writes a nested OutputArchive under the given key to this OutputArchive.

void save_to(const std::string &filename)#

Saves the OutputArchive into a serialized representation in a file at filename.

void save_to(std::ostream &stream)#

Saves the OutputArchive into a serialized representation into the given stream.

void save_to(const std::function<size_t(const void*, size_t)> &func)#

Saves the OutputArchive into a serialized representation using the given writer function.

template<typename ...Ts>
inline void operator()(Ts&&... ts)#

Forwards all arguments to write().

Useful for generic code that can be reused for both OutputArchive and InputArchive (where operator() forwards to read()).

Example:

torch::serialize::OutputArchive archive;
archive.write("tensor1", tensor1);
archive.write("tensor2", tensor2);
archive.save_to("multi_tensor.pt");

InputArchive#

class InputArchive#

A recursive representation of tensors that can be deserialized from a file or stream.

In most cases, users should not have to interact with this class, and should instead use torch::load.

Public Functions

InputArchive()#

Default-constructs the InputArchive.

InputArchive(InputArchive&&) = default#
InputArchive &operator=(InputArchive&&) = default#
InputArchive(InputArchive&) = delete#
InputArchive &operator=(InputArchive&) = delete#
~InputArchive() = default#
void read(const std::string &key, c10::IValue &ivalue)#

Reads an IValue associated with a given key.

bool try_read(const std::string &key, c10::IValue &ivalue)#

Reads an IValue associated with a given key.

If there is no IValue associated with the key, this returns false, otherwise it returns true.

bool try_read(const std::string &key, Tensor &tensor, bool is_buffer = false)#

Reads a tensor associated with a given key.

If there is no tensor associated with the key, this returns false, otherwise it returns true. If the tensor is expected to be a buffer (not differentiable), is_buffer must be true.

void read(const std::string &key, Tensor &tensor, bool is_buffer = false)#

Reads a tensor associated with a given key.

If the tensor is expected to be a buffer (not differentiable), is_buffer must be true.

bool try_read(const std::string &key, InputArchive &archive)#

Reads a InputArchive associated with a given key.

If there is no InputArchive associated with the key, this returns false, otherwise it returns true.

void read(const std::string &key, InputArchive &archive)#

Reads an InputArchive associated with a given key.

The archive can thereafter be used for further deserialization of the nested data.

void load_from(const std::string &filename, std::optional<torch::Device> device = std::nullopt)#

Loads the InputArchive from a serialized representation stored in the file at filename.

Storage are remapped using device option. If device is not specified, the module is loaded to the original device.

void load_from(std::istream &stream, std::optional<torch::Device> device = std::nullopt)#

Loads the InputArchive from a serialized representation stored in the given stream.

Storage are remapped using device option. If device is not specified, the module is loaded to the original device.

void load_from(const char *data, size_t size, std::optional<torch::Device> device = std::nullopt)#
void load_from(const std::function<size_t(uint64_t pos, void *buf, size_t nbytes)> &read_func, const std::function<size_t(void)> &size_func, std::optional<torch::Device> device = std::nullopt)#
std::vector<std::string> keys()#
template<typename ...Ts>
inline void operator()(Ts&&... ts)#

Forwards all arguments to read().

Useful for generic code that can be reused for both InputArchive and OutputArchive (where operator() forwards to write()).

Example:

torch::serialize::InputArchive archive;
archive.load_from("multi_tensor.pt");

torch::Tensor tensor1, tensor2;
archive.read("tensor1", tensor1);
archive.read("tensor2", tensor2);

Saving Multiple Values#

Archives are useful when you need to save multiple related values together:

// Save multiple tensors and metadata
torch::serialize::OutputArchive out_archive;
out_archive.write("weights", model_weights);
out_archive.write("biases", model_biases);
out_archive.write("epoch", torch::tensor(current_epoch));
out_archive.write("loss", torch::tensor(best_loss));
out_archive.save_to("training_state.pt");

// Load them back
torch::serialize::InputArchive in_archive;
in_archive.load_from("training_state.pt");

torch::Tensor weights, biases, epoch_tensor, loss_tensor;
in_archive.read("weights", weights);
in_archive.read("biases", biases);
in_archive.read("epoch", epoch_tensor);
in_archive.read("loss", loss_tensor);

int epoch = epoch_tensor.item<int>();
float loss = loss_tensor.item<float>();