Getting started with PyTorch
Quick answer
PyTorch is a deep learning framework built around tensors (like NumPy arrays but GPU-accelerated) and automatic differentiation via autograd. Install it with the official command from pytorch.org for your CUDA version, create tensors with torch.tensor, define models by subclassing nn.Module, and train with an optimizer and a loss in a manual loop. Its define-by-run graph makes it easy to debug.
Quickstart - PyTorch
Install PyTorch on your machine. If you have Anaconda installed, you can install PyTorch by running the following command:
conda install pytorch torchvision -c pytorch
Import PyTorch in your Python script by adding the following line at the top:
import torch
Check if PyTorch is working by running the following code:
x = torch.Tensor([5, 3])
y = torch.Tensor([2, 1])
print(x*y)This should print tensor([10., 3.])
PyTorch uses tensors, which are similar to NumPy's ndarrays, to store and manipulate data. You can create a tensor by passing a list or array to the torch.Tensor function. For example:
x = torch.Tensor([[1, 2, 3], [4, 5, 6]])
print(x)This should print ```tensor([[1., 2., 3.], [4., 5., 6.]])``
You can also create tensors with random values using the torch.rand function. For example:
x = torch.rand(3, 3)
print(x)This will create a 3x3 tensor with random values between 0 and 1.
You can perform mathematical operations on tensors just like you would with NumPy arrays. For example:
x = torch.Tensor([[1, 2, 3], [4, 5, 6]])
y = torch.Tensor([[1, 1, 1], [2, 2, 2]])
z = x + y
print(z)This should print ```tensor([[2., 3., 4.], [6., 7., 8.]])``
You can also perform operations on tensors using PyTorch's built-in functions. For example:
x = torch.Tensor([[1, 2, 3], [4, 5, 6]])
y = torch.mean(x, dim=1)
print(y)This should print tensor([2., 5.]), which is the mean of each row of x.
I hope this tutorial helps you get started with PyTorch. For more details visit PyTorch github Documentation
Software Engineering Leader & Technical Author · Updated July 21, 2026