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arXiv · 1909.04029

The surrogate matrix methodology: A reference implementation for low-cost assembly in isogeometric analysis

Daniel Drzisga·Brendan Keith·Barbara Wohlmuth
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Abstract

A reference implementation of a new method in isogeometric analysis (IGA) is presented. It delivers low-cost variable-scale approximations (surrogates) of the matrices which IGA conventionally requires to be computed by element-scale quadrature. To generate surrogate matrices, quadrature must only be performed on a fraction of the elements in the computational domain. In this way, quadrature determines only a subset of the entries in the final matrix. The remaining matrix entries are computed by a simple B-spline interpolation procedure. We present the modifications and extensions required for a reference implementation in the open-source IGA software library GeoPDEs. The exposition is fashioned to help facilitate similar modifications in other contemporary software libraries.

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Daniel Drzisga, Brendan Keith, Barbara Wohlmuth. 2019-09-08. The surrogate matrix methodology: A reference implementation for low-cost assembly in isogeometric analysis. https://doi.org/10.1016/j.mex.2020.100813

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