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arXiv · 2105.09469

Decomposing reverse-mode automatic differentiation

Roy Frostig·Matthew J. Johnson·Dougal Maclaurin·Adam Paszke·Alexey Radul
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Abstract

We decompose reverse-mode automatic differentiation into (forward-mode) linearization followed by transposition. Doing so isolates the essential difference between forward- and reverse-mode AD, and simplifies their joint implementation. In particular, once forward-mode AD rules are defined for every primitive operation in a source language, only linear primitives require an additional transposition rule in order to arrive at a complete reverse-mode AD implementation. This is how reverse-mode AD is written in JAX and Dex.

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Roy Frostig, Matthew J. Johnson, Dougal Maclaurin, Adam Paszke, Alexey Radul. 2021-05-20. Decomposing reverse-mode automatic differentiation. https://arxiv.org/abs/2105.09469

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