You can implement a sparse autoencoder in PyTorch for dimensionality reduction:

In the above code, we are using the following:
- Sparse Autoencoder: Combines a reconstruction loss (MSELoss) with a sparsity loss (KL divergence) to enforce sparsity on the hidden layer activations.
- Training Loop: Optimizes the model to reconstruct input data while encouraging sparse representations in the hidden layer.
Hence, By referring to above you can implement a sparse autoencoder in PyTorch for dimensionality reduction.