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arXiv · 2312.12967

Implementation of the Emulator-based Component Analysis

Anton Vladyka·Eemeli A. Eronen·Johannes Niskanen
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Abstract

We present a PyTorch-powered implementation of the emulator-based component analysis used for ill-posed numerical non-linear inverse problems, where an approximate emulator for the forward problem is known. This emulator may be a numerical model, an interpolating function, or a fitting function such as a neural network. With the help of the emulator and a data set, the method seeks dimensionality reduction by projection in the variable space so that maximal variance of the target (response) values of the data is covered. The obtained basis set for projection in the variable space defines a subspace of the greatest response for the outcome of the forward problem. The method allows for the reconstruction of the coordinates in this subspace for an approximate solution to the inverse problem. We present an example of using the code provided as a Python class.

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Anton Vladyka, Eemeli A. Eronen, Johannes Niskanen. 2024-08-23. Implementation of the Emulator-based Component Analysis. https://doi.org/10.1016/j.jocs.2024.102437

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