nops 0.3.0

nops: Neural Operators made simple — with physics-informed losses for FNO, DeepONet, and GNO

Neural Operators made simple.

graph LR
    subgraph nops_FNO [nops: FNO Architecture]
        direction LR
        Input["Input<br/>(Batch, C_in, X, Y...)"] --> Grid{Append<br/>Grid?}
        Grid -- Yes --> InputGrid[Input + Grid]
        Grid -- No --> InputGrid
        
        InputGrid --> Lifting["Lifting Layer<br/>(Projection P)"]
        
        subgraph FourierLayers [Fourier Layers x N]
            direction TB
            FFT[FFT] --> SpecConv["Spectral Conv<br/>(R * Weights)"]
            SpecConv --> iFFT["Inverse FFT"]
            iFFT --> Skip{"Skip<br/>Connection"}
            
            Skip --> Attention{"Attention<br/>Gating?"}
            Attention -- Yes --> AttnBlock["Attention Weights"]
            Attention -- No --> SumBlock["Sum"]
            
            AttnBlock --> OutputLayer
            SumBlock --> OutputLayer
        end
        
        Lifting --> FourierLayers
        FourierLayers --> Projection["Projection Layer<br/>(Q)"]
        Projection --> Output["Output<br/>(Batch, C_out, X, Y...)"]
    end

A human-centric interface for operating with Neural Operators (FNO, GNO, DeepONet, etc.).

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nops is designed to be an elegant, high-level layer over complex neural operator architectures. Whether you are a researcher prototyping a new PDE solver or an engineer deploying a model to production, nops abstracts the complexity while retaining the flexibility you need.

✨ Features

• Human-Friendly API: Intuitive classes and methods that make sense.
• Multi-Dimensional: Seamless support for 1D, 2D, and 3D FNO models.
• Production Ready: Built with modularity, type hinting, and efficiency in mind.
• Batteries Included:
• Attention Gating: Advanced mechanisms to weight parallel Fourier branches.
• Flexible Gridding: Automatic handling of grid coordinates.
• Padding Management: Easy handling of boundary conditions.

📦 Installation

Install nops easily via pip:

pip install nops

Note: Requires Python 3.12+

🚀 Quick Start

Solving a PDE with a Fourier Neural Operator (FNO) has never been this simple.

import torch
import torch.nn as nn
from nops.fno.models.original import FNO

# 1. Define your configuration
model = FNO(
    modes=[16, 16],               # 16 Fourier modes for height and width
    num_fourier_layers=4,         # Depth of the network
    in_channels=3,                # (e.g., u, v, p)
    out_channels=1,               # (e.g., pressure field)
    lifting_channels=64,
    projection_channels=64,
    mid_channels=64,
    activation=nn.GELU(),
    add_grid=True,                # Auto-append x,y coordinates
    attn_gating=True              # Enable attention mechanism
)

# 2. Forward pass
# Batch size: 8, Channels: 3, Resolution: 128x128
input_data = torch.randn(8, 3, 128, 128)
output = model(input_data)

print(f"Output Field Shape: {output.shape}")
# > Output Field Shape: torch.Size([8, 1, 128, 128])

🗺️ Roadmap

• FNO (Fourier Neural Operator): Original implementation with attention extensions.
• DeepONet: Implementation of Deep Operator Networks.
• GNO (Graph Neural Operator): Support for irregular meshes.
• Physics-Informed Losses: Built-in loss functions for PDE constraints.
• Data Loaders: Standard datasets (Burgers, Navier-Stokes, Darcy Flow).

🤝 Contributing

We welcome contributions! nops is a community-driven project to make neural operators accessible to everyone.

1. Fork the repository.
2. Create a Feature Branch (git checkout -b feature/AmazingFeature).
3. Commit your changes (git commit -m 'Add some AmazingFeature').
4. Push to the branch (git push origin feature/AmazingFeature).
5. Open a Pull Request.

Please ensure your code follows the existing style and includes tests.

📄 License

Distributed under the MIT License. See LICENSE for more information.

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_{Built with ❤️ by the nops community.}