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TL;DR
Ignite is a high-level library to help with training and evaluating neural networks in PyTorch flexibly and transparently.
_Click on the image to see complete code_
Features
-
Less code than pure PyTorch while ensuring maximum control and simplicity
-
Library approach and no program's control inversion - Use ignite where and when you need
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Extensible API for metrics, experiment managers, and other components
Table of Contents
- Table of Contents
- Why Ignite?
- Installation
- Getting Started
- Documentation
- Examples
- Communication
- Contributing
- Projects using Ignite
- Citing Ignite
- About the team & Disclaimer
Why Ignite?
Ignite is a library that provides three high-level features:
- Extremely simple engine and event system
- Out-of-the-box metrics to easily evaluate models
- Built-in handlers to compose training pipeline, save artifacts and log parameters and metrics
Simplified training and validation loop
No more coding for/while loops on epochs and iterations. Users instantiate engines and run them.
Example
```python from ignite.engine import Engine, Events, create_supervised_evaluator from ignite.metrics import Accuracy # Setup training engine: def train_step(engine, batch): # Users can do whatever they need on a single iteration # Eg. forward/backward pass for any number of models, optimizers, etc # ... trainer = Engine(train_step) # Setup single model evaluation engine evaluator = create_supervised_evaluator(model, metrics={"accuracy": Accuracy()}) def validation(): state = evaluator.run(validation_data_loader) # print computed metrics print(trainer.state.epoch, state.metrics) # Run model's validation at the end of each epoch trainer.add_event_handler(Events.EPOCH_COMPLETED, validation) # Start the training trainer.run(training_data_loader, max_epochs=100) ```Power of Events & Handlers
The cool thing with handlers is that they offer unparalleled flexibility (compared to, for example, callbacks). Handlers can be any function: e.g. lambda, simple function, class method, etc. Thus, we do not require to inherit from an interface and override its abstract methods which could unnecessarily bulk up your code and its complexity.
Execute any number of functions whenever you wish
Examples
```python trainer.add_event_handler(Events.STARTED, lambda _: print("Start training")) # attach handler with args, kwargs mydata = [1, 2, 3, 4] logger = ... def on_training_ended(data): print(f"Training is ended. mydata={data}") # User can use variables from another scope logger.info("Training is ended") trainer.add_event_handler(Events.COMPLETED, on_training_ended, mydata) # call any number of functions on a single event trainer.add_event_handler(Events.COMPLETED, lambda engine: print(engine.state.times)) @trainer.on(Events.ITERATION_COMPLETED) def log_something(engine): print(engine.state.output) ```Built-in events filtering
Examples
```python # run the validation every 5 epochs @trainer.on(Events.EPOCH_COMPLETED(every=5)) def run_validation(): # run validation # change some training variable once on 20th epoch @trainer.on(Events.EPOCH_STARTED(once=20)) def change_training_variable(): # ... # Trigger handler with customly defined frequency @trainer.on(Events.ITERATION_COMPLETED(event_filter=first_x_iters)) def log_gradients(): # ... ```Stack events to share some actions
Examples
Events can be stacked together to enable multiple calls: ```python @trainer.on(Events.COMPLETED | Events.EPOCH_COMPLETED(every=10)) def run_validation(): # ... ```Custom events to go beyond standard events
Examples
Custom events related to backward and optimizer step calls: ```python from ignite.engine import EventEnum class BackpropEvents(EventEnum): BACKWARD_STARTED = 'backward_started' BACKWARD_COMPLETED = 'backward_completed' OPTIM_STEP_COMPLETED = 'optim_step_completed' def update(engine, batch): # ... loss = criterion(y_pred, y) engine.fire_event(BackpropEvents.BACKWARD_STARTED) loss.backward() engine.fire_event(BackpropEvents.BACKWARD_COMPLETED) optimizer.step() engine.fire_event(BackpropEvents.OPTIM_STEP_COMPLETED) # ... trainer = Engine(update) trainer.register_events(*BackpropEvents) @trainer.on(BackpropEvents.BACKWARD_STARTED) def function_before_backprop(engine): # ... ``` - Complete snippet is found [here](https://pytorch.org/ignite/faq.html#creating-custom-events-based-on-forward-backward-pass). - Another use-case of custom events: [trainer for Truncated Backprop Through Time](https://pytorch.org/ignite/contrib/engines.html#ignite.contrib.engines.create_supervised_tbptt_trainer).Out-of-the-box metrics
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Metrics for various tasks: Precision, Recall, Accuracy, Confusion Matrix, IoU etc, ~20 regression metrics.
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Users can also compose their metrics with ease from existing ones using arithmetic operations or torch methods.
Example
```python precision = Precision(average=False) recall = Recall(average=False) F1_per_class = (precision * recall * 2 / (precision + recall)) F1_mean = F1_per_class.mean() # torch mean method F1_mean.attach(engine, "F1") ```Installation
From pip:
pip install pytorch-igniteFrom conda:
conda install ignite -c pytorchFrom source:
pip install git+https://github.com/pytorch/igniteNightly releases
From pip:
pip install --pre pytorch-igniteFrom conda (this suggests to install pytorch nightly release instead of stable version as dependency):
conda install ignite -c pytorch-nightlyDocker Images
Using pre-built images
Pull a pre-built docker image from our Docker Hub and run it with docker v19.03+.
docker run --gpus all -it -v $PWD:/workspace/project --network=host --shm-size 16G pytorchignite/base:latest /bin/bashList of available pre-built images
Base - `pytorchignite/base:latest` - `pytorchignite/apex:latest` - `pytorchignite/hvd-base:latest` - `pytorchignite/hvd-apex:latest` - `pytorchignite/msdp-apex:latest` Vision: - `pytorchignite/vision:latest` - `pytorchignite/hvd-vision:latest` - `pytorchignite/apex-vision:latest` - `pytorchignite/hvd-apex-vision:latest` - `pytorchignite/msdp-apex-vision:latest` NLP: - `pytorchignite/nlp:latest` - `pytorchignite/hvd-nlp:latest` - `pytorchignite/apex-nlp:latest` - `pytorchignite/hvd-apex-nlp:latest` - `pytorchignite/msdp-apex-nlp:latest`For more details, see here.
Getting Started
Few pointers to get you started:
- Quick Start Guide: Essentials of getting a project up and running
- Concepts of the library: Engine, Events & Handlers, State, Metrics
- Full-featured template examples (coming soon)
Documentation
- Stable API documentation and an overview of the library: https://pytorch.org/ignite/
- Development version API documentation: https://pytorch.org/ignite/master/
- FAQ, "Questions on Github" and "Questions on Discuss.PyTorch".
- Project's Roadmap
Additional Materials
- Distributed Training Made Easy with PyTorch-Ignite
- PyTorch Ecosystem Day 2021 Breakout session presentation
- Tutorial blog post about PyTorch-Ignite
- 8 Creators and Core Contributors Talk About Their Model Training Libraries From PyTorch Ecosystem
- Ignite Posters from Pytorch Developer Conferences:
Examples
Tutorials
Text Classification using Convolutional Neural
Networks- Variational Auto
Encoders
- Convolutional Neural Networks for Classifying Fashion-MNIST
Dataset
- Training Cycle-GAN on Horses to
Zebras with Nvidia/Apex - logs on W&B
- Another training Cycle-GAN on Horses to
Zebras with Native Torch CUDA AMP - logs on W&B
- Finetuning EfficientNet-B0 on
CIFAR100
- Hyperparameters tuning with
Ax
- Basic example of LR finder on
MNIST
- Benchmark mixed precision training on Cifar100:
torch.cuda.amp vs nvidia/apex
- MNIST training on a single
TPU
- CIFAR10 Training on multiple TPUs
- Basic example of handlers
time profiling on MNIST training example
Reproducible Training Examples
Inspired by torchvision/references, we provide several reproducible baselines for vision tasks:
- ImageNet - logs on Ignite Trains server coming soon ...
- Pascal VOC2012 - logs on Ignite Trains server coming soon ...
Features:
- Distributed training: native or horovod and using PyTorch native AMP
Code-Generator application
The easiest way to create your training scripts with PyTorch-Ignite:
Communication
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GitHub issues: questions, bug reports, feature requests, etc.
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Discuss.PyTorch, category "Ignite".
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PyTorch-Ignite Discord Server: to chat with the community
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GitHub Discussions: general library-related discussions, ideas, Q&A, etc.
User feedback
We have created a form for "user feedback". We appreciate any type of feedback, and this is how we would like to see our community:
- If you like the project and want to say thanks, this the right place.
- If you do not like something, please, share it with us, and we can see how to improve it.
Thank you!
Contributing
Please see the contribution guidelines for more information.
As always, PRs are welcome :)
Projects using Ignite
Research papers
- [BatchBALD: Efficient and Diverse Batch Acquisition for Deep Bayesian Active Learning](https://github.com/BlackHC/BatchBALD) - [A Model to Search for Synthesizable Molecules](https://github.com/john-bradshaw/molecule-chef) - [Localised Generative Flows](https://github.com/jrmcornish/lgf) - [Extracting T Cell Function and Differentiation Characteristics from the Biomedical Literature](https://github.com/hammerlab/t-cell-relation-extraction) - [Variational Information Distillation for Knowledge Transfer](https://github.com/amzn/xfer/tree/master/var_info_distil) - [XPersona: Evaluating Multilingual Personalized Chatbot](https://github.com/HLTCHKUST/Xpersona) - [CNN-CASS: CNN for Classification of Coronary Artery Stenosis Score in MPR Images](https://github.com/ucuapps/CoronaryArteryStenosisScoreClassification) - [Bridging Text and Video: A Universal Multimodal Transformer for Video-Audio Scene-Aware Dialog](https://github.com/ictnlp/DSTC8-AVSD) - [Adversarial Decomposition of Text Representation](https://github.com/text-machine-lab/adversarial_decomposition) - [Uncertainty Estimation Using a Single Deep Deterministic Neural Network](https://github.com/y0ast/deterministic-uncertainty-quantification) - [DeepSphere: a graph-based spherical CNN](https://github.com/deepsphere/deepsphere-pytorch) - [Norm-in-Norm Loss with Faster Convergence and Better Performance for Image Quality Assessment](https://github.com/lidq92/LinearityIQA) - [Unified Quality Assessment of In-the-Wild Videos with Mixed Datasets Training](https://github.com/lidq92/MDTVSFA) - [Deep Signature Transforms](https://github.com/patrick-kidger/Deep-Signature-Transforms) - [Neural CDEs for Long Time-Series via the Log-ODE Method](https://github.com/jambo6/neuralCDEs-via-logODEs) - [Volumetric Grasping Network](https://github.com/ethz-asl/vgn) - [Mood Classification using Listening Data](https://github.com/fdlm/listening-moods) - [Deterministic Uncertainty Estimation (DUE)](https://github.com/y0ast/DUE) - [PyTorch-Hebbian: facilitating local learning in a deep learning framework](https://github.com/Joxis/pytorch-hebbian) - [Stochastic Weight Matrix-Based Regularization Methods for Deep Neural Networks](https://github.com/rpatrik96/lod-wmm-2019) - [Learning explanations that are hard to vary](https://github.com/gibipara92/learning-explanations-hard-to-vary) - [The role of disentanglement in generalisation](https://github.com/mmrl/disent-and-gen) - [A Probabilistic Programming Approach to Protein Structure Superposition](https://github.com/LysSanzMoreta/Theseus-PP) - [PadChest: A large chest x-ray image dataset with multi-label annotated reports](https://github.com/auriml/Rx-thorax-automatic-captioning)Blog articles, tutorials, books
- [State-of-the-Art Conversational AI with Transfer Learning](https://github.com/huggingface/transfer-learning-conv-ai) - [Tutorial on Transfer Learning in NLP held at NAACL 2019](https://github.com/huggingface/naacl_transfer_learning_tutorial) - [Deep-Reinforcement-Learning-Hands-On-Second-Edition, published by Packt](https://github.com/PacktPublishing/Deep-Reinforcement-Learning-Hands-On-Second-Edition) - [Once Upon a Repository: How to Write Readable, Maintainable Code with PyTorch](https://towardsdatascience.com/once-upon-a-repository-how-to-write-readable-maintainable-code-with-pytorch-951f03f6a829) - [The Hero Rises: Build Your Own SSD](https://allegro.ai/blog/the-hero-rises-build-your-own-ssd/) - [Using Optuna to Optimize PyTorch Ignite Hyperparameters](https://medium.com/pytorch/using-optuna-to-optimize-pytorch-ignite-hyperparameters-626ffe6d4783) - [PyTorch Ignite - Classifying Tiny ImageNet with EfficientNet](https://towardsdatascience.com/pytorch-ignite-classifying-tiny-imagenet-with-efficientnet-e5b1768e5e8f)Toolkits
- [Project MONAI - AI Toolkit for Healthcare Imaging](https://github.com/Project-MONAI/MONAI) - [DeepSeismic - Deep Learning for Seismic Imaging and Interpretation](https://github.com/microsoft/seismic-deeplearning) - [Nussl - a flexible, object-oriented Python audio source separation library](https://github.com/nussl/nussl) - [PyTorch Adapt - A fully featured and modular domain adaptation library](https://github.com/KevinMusgrave/pytorch-adapt) - [gnina-torch: PyTorch implementation of GNINA scoring function](https://github.com/RMeli/gnina-torch)Others
- [Implementation of "Attention is All You Need" paper](https://github.com/akurniawan/pytorch-transformer) - [Implementation of DropBlock: A regularization method for convolutional networks in PyTorch](https://github.com/miguelvr/dropblock) - [Kaggle Kuzushiji Recognition: 2nd place solution](https://github.com/lopuhin/kaggle-kuzushiji-2019) - [Unsupervised Data Augmentation experiments in PyTorch](https://github.com/vfdev-5/UDA-pytorch) - [Hyperparameters tuning with Optuna](https://github.com/optuna/optuna-examples/blob/main/pytorch/pytorch_ignite_simple.py) - [Logging with ChainerUI](https://chainerui.readthedocs.io/en/latest/reference/module.html#external-library-support) - [FixMatch experiments in PyTorch and Ignite (CTA dataaug policy)](https://github.com/vfdev-5/FixMatch-pytorch) - [Kaggle Birdcall Identification Competition: 1st place solution](https://github.com/ryanwongsa/kaggle-birdsong-recognition) - [Logging with Aim - An open-source experiment tracker](https://aimstack.readthedocs.io/en/latest/quick_start/integrations.html#integration-with-pytorch-ignite)See other projects at "Used by"
If your project implements a paper, represents other use-cases not covered in our official tutorials, Kaggle competition's code, or just your code presents interesting results and uses Ignite. We would like to add your project to this list, so please send a PR with brief description of the project.
Citing Ignite
If you use PyTorch-Ignite in a scientific publication, we would appreciate citations to our project.
@misc{pytorch-ignite,
author = {V. Fomin and J. Anmol and S. Desroziers and J. Kriss and A. Tejani},
title = {High-level library to help with training neural networks in PyTorch},
year = {2020},
publisher = {GitHub},
journal = {GitHub repository},
howpublished = {\url{https://github.com/pytorch/ignite}},
}About the team & Disclaimer
PyTorch-Ignite is a NumFOCUS Affiliated Project, operated and maintained by volunteers in the PyTorch community in their capacities as individuals (and not as representatives of their employers). See the "About us" page for a list of core contributors. For usage questions and issues, please see the various channels here. For all other questions and inquiries, please send an email to contact@pytorch-ignite.ai.