An efficient spectral interpolation routine for the TwoPunctures code

TL;DR

This paper introduces a new spectral interpolation routine for the TwoPunctures code that significantly enhances performance, reducing runtime by approximately 100 times while maintaining high accuracy, and provides installation guidance.

Contribution

A novel spectral interpolation routine for TwoPunctures that drastically improves efficiency and is compatible with both standalone and Einstein Toolkit versions.

Findings

Performance improved by a factor of ~100

Results are consistent with original routine to roundoff precision

Provides installation guidance for different code versions

Abstract

TwoPunctures is perhaps the most widely-adopted code for generating binary black hole "puncture" initial data and interpolating these (spectral) data onto evolution grids. In typical usage, the bulk of this code's run time is spent in its spectral interpolation routine. We announce a new publicly-available spectral interpolation routine that improves the performance of the original interpolation routine by a factor of ~100, yielding results consistent with the original spectral interpolation routine to roundoff precision. This note serves as a guide for installing this routine both in the original standalone TwoPunctures code and the Einstein Toolkit supported version of this code.