Generator — PyTorch 2.7 documentation (original) (raw)

class torch.Generator(device='cpu')

Creates and returns a generator object that manages the state of the algorithm which produces pseudo random numbers. Used as a keyword argument in many In-place random samplingfunctions.

Parameters

device (torch.device, optional) – the desired device for the generator.

Returns

An torch.Generator object.

Return type

Generator

Example:

g_cpu = torch.Generator() g_cuda = torch.Generator(device='cuda')

clone_state() → torch.Generator

Clones the current state of the generator and returns a new generator pointing to this cloned state. This method is beneficial for preserving a particular state of a generator to restore at a later point.

Returns

A Generator pointing to the newly cloned state.

Return type

torch.Generator

Example

g_cuda = torch.Generator(device='cuda') cloned_state = g_cuda.clone_state()

device

Generator.device -> device

Gets the current device of the generator.

Example:

g_cpu = torch.Generator() g_cpu.device device(type='cpu')

get_state() → Tensor

Returns the Generator state as a torch.ByteTensor.

Returns

A torch.ByteTensor which contains all the necessary bits to restore a Generator to a specific point in time.

Return type

Tensor

Example:

g_cpu = torch.Generator() g_cpu.get_state()

graphsafe_get_state() → torch.Generator

Retrieves the current state of the generator in a manner that is safe for graph capture. This method is crucial for ensuring that the generator’s state can be captured in the CUDA graph.

Returns

A Generator point to the current state of the generator

Return type

torch.Generator

Example

g_cuda = torch.Generator(device='cuda') current_state = g_cuda.graphsafe_get_state()

graphsafe_set_state(state) → None

Sets the state of the generator to the specified state in a manner that is safe for use in graph capture. This method is crucial for ensuring that the generator’s state can be captured in the CUDA graph.

Parameters

state (torch.Generator) – A Generator point to the new state for the generator, typically obtained from graphsafe_get_state.

Example

g_cuda = torch.Generator(device='cuda') g_cuda_other = torch.Generator(device='cuda') current_state = g_cuda_other.graphsafe_get_state() g_cuda.graphsafe_set_state(current_state)

initial_seed() → int

Returns the initial seed for generating random numbers.

Example:

g_cpu = torch.Generator() g_cpu.initial_seed() 2147483647

manual_seed(seed) → Generator

Sets the seed for generating random numbers. Returns a torch.Generator object. Any 32-bit integer is a valid seed.

Parameters

seed (int) – The desired seed. Value must be within the inclusive range[-0x8000_0000_0000_0000, 0xffff_ffff_ffff_ffff]. Otherwise, a RuntimeError is raised. Negative inputs are remapped to positive values with the formula0xffff_ffff_ffff_ffff + seed.

Returns

An torch.Generator object.

Return type

Generator

Example:

g_cpu = torch.Generator() g_cpu.manual_seed(2147483647)

seed() → int

Gets a non-deterministic random number from std::random_device or the current time and uses it to seed a Generator.

Example:

g_cpu = torch.Generator() g_cpu.seed() 1516516984916

set_state(new_state) → void

Sets the Generator state.

Parameters

new_state (torch.ByteTensor) – The desired state.

Example:

g_cpu = torch.Generator() g_cpu_other = torch.Generator() g_cpu.set_state(g_cpu_other.get_state())