PyTorch torch.add Function


Pytorch torch 参考手册Pytorch torch Reference Manual

torch.addis a function in PyTorch used to perform element-wise addition. It adds two tensors or a tensor and a scalar.

This is one of the most basic mathematical operations and is used in various computation scenarios in deep learning.

Function Definition

torch.add(input, other, alpha=1, out=None)

Parameters:

  • input(Tensor): The first input tensor.
  • other(Tensor or float): The second input tensor or scalar.
  • alpha(float, optional): scaling factor,otherwhich is multiplied by this value and then added toinputit, default is 1.
  • out(Tensor, optional): output tensor.

Return Value:

  • torch.Tensor: Returns the tensor after addition.

Usage Examples

Example 1: Adding Two Tensors

Example

import torch

# Create two tensors
a = torch.tensor([1, 2, 3])
b = torch.tensor([4, 5, 6])

# Add them
c = torch.add(a, b)

print(c)

The output is:

tensor([5, 7, 9])

Example 2: Tensor Plus Scalar

Example

import torch

# Create a tensor
a = torch.tensor([1, 2, 3])

# Add the scalar
b = torch.add(a, 10)

print(b)

The output is:

tensor([11, 12, 13])

Example 3: Using the alpha Parameter

Example

import torch

# Create two tensors
a = torch.tensor([1.0, 2.0, 3.0])
b = torch.tensor([1.0, 2.0, 3.0])

# Compute a + 2 * b
c = torch.add(a, b, alpha=2)

print(c)

The output is:

tensor([3., 6., 9.])

alphaThe parameter is useful when implementing certain algorithms, such as computinginput + alpha * other。

Example 4: Broadcasting Mechanism

Example

import torch

# Add tensors of different shapes (broadcasting)
a = torch.tensor([[1, 2, 3], [4, 5, 6]])
b = torch.tensor([1, 2, 3])

c = torch.add(a, b)

print(c)

The output is:

tensor([[2, 4, 6],
        [5, 7, 9])

PyTorch supports the broadcasting mechanism, which allows tensors of different shapes to be operated on.


Using the Plus Operator

In addition to using thetorch.add()function, you can also directly use the+operator, and the two have the same effect:

Example

import torch

a = torch.tensor([1, 2, 3])
b = torch.tensor([4, 5, 6])

# The two methods are equivalent
c1 = torch.add(a, b)
c2 = a + b

print(c1)
print(c2)
print(torch.equal(c1, c2))

Pytorch torch 参考手册Pytorch torch Reference Manual

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