PyTorch torch.is_tensor Function

torch.is_tensoris a utility function in PyTorch used to check whether a given object is a tensor.

In deep learning and scientific computing, tensors are the most fundamental data structure, so being able to quickly determine whether an object is a tensor is very useful.

Function Definition

torch.is_tensor(obj)

Parameter:

obj(any type): The object to check.

Return Value:

bool: ifobjis a PyTorch tensor, returnsTrue; otherwise, returnFalse。

Usage Examples

The following are some uses oftorch.is_tensorAn example of the function to help you better understand how it works.

Example 1: Check Tensor

Example

import torch

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

# Check if it is a tensor
result = torch.is_tensor(tensor)
print(result) # Output: True

The output result is:

True

In this example, we created a PyTorch tensor and usedtorch.is_tensorThe function checks whether it is a tensor. Sincetensorit is indeed a tensor, the function returnsTrue。

Example 2: Check Non-Tensor Object

Example

import torch

# Create a Python list
python_list = [1, 2, 3]

# Check if it is a tensor
result = torch.is_tensor(python_list)
print(result) # Output: False

The output result is:

False

In this example, we created a Python list and usedtorch.is_tensorThe function checks whether it is a tensor. Sincepython_listis not a PyTorch tensor, the function returnsFalse。

Example 3: Check Other Types of Objects

Example

import torch
import numpy as np

# Create a NumPy array
numpy_array = np.array([1, 2, 3])

# Check if it is a tensor
result = torch.is_tensor(numpy_array)
print(result) # Output: False

The output result is:

False

In this example, we created a NumPy array and usedtorch.is_tensorThe function checks whether it is a PyTorch tensor. Sincenumpy_arrayis a NumPy array rather than a PyTorch tensor, the function returnsFalse。

Use Cases

torch.is_tensorThe function is typically very useful in the following scenarios:

Debug Code: When you need to confirm whether a variable is a PyTorch tensor, you can use this function for a quick check.
Type Checking: When writing functions that need to handle multiple data types, usingtorch.is_tensorcan ensure that the passed-in parameter is a PyTorch tensor.
Conditional Judgment: When performing different operations based on data types in a program,torch.is_tensorcan help you make conditional judgments.

Notes

torch.is_tensorcan only check whether an object is a PyTorch tensor and cannot be used to check other types of tensors (such as NumPy arrays).
If you need to check whether an object is a NumPy array, you can useisinstance(obj, np.ndarray)。

Pytorch torch Reference Manual