Comgra: A library for debugging and understanding neural networks
I'm a machine learning engineer and researcher. I got fed up with how difficult it is to understand why neural networks behave the way they do, so i wrote a library to help with it. Comgra (computation graph analysis) is a library you can use with pytorch to extract all the tensor data you care about and visualize it graphically in a browser. This allows for a much more detailed analysis of what is happening than the usual approach of using tensorboard. You can go investigate tensors as training proceeds, drill down into individual neurons, inspect single data sets that are of special…
In plain words
Comgra is a Python library for PyTorch that helps machine learning engineers and researchers understand neural network behavior by extracting tensor data and visualizing it in a browser-based interface. It allows users to inspect individual neurons, track gradients, compare training runs, and drill down into specific datasets during training—offering more detailed analysis than standard tools like TensorBoard. The library is designed to speed up hypothesis testing and reveal how different network components interact.
written from the facts on this page · September 2026
From the sources
In the maker’s words, at launch
I'm a machine learning engineer and researcher. I got fed up with how difficult it is to understand why neural networks behave the way they do, so i wrote a library to help with it. Comgra (computation graph analysis) is a library you can use with pytorch to extract all the tensor data you care about and visualize it graphically in a browser. This allows for a much more detailed analysis of what is happening than the usual approach of using tensorboard. You can go investigate tensors as training proceeds, drill down into individual neurons, inspect single data sets that are of special interest to you, track gradients, compare statistics between different training runs, and more. This tool has saved me a ton of time in my research by letting me check my hypotheses much more quickly than normal and by helping me understand how the different parts of my network really interact. I hope this tool can save other people just as much time as it did me. I'm also open for suggestions on how to improve it further: Since I'm already gathering and visualizing a lot of network information, adding more automated analysis would not be much extra work.
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