Abstract

This thorn is a test driver for interpolation. It sets up a bunch of Cactus grid arrays with known (analytic) smooth functions, then interpolates them on a finer grid of points, and finally compares the results to the analytic functions. It can be used either to examine in detail the performance and accuracy of an interpolator, and/or in a Cactus test suite to quickly verify correct operation of the interpolator.

At present TestInterp knows how to test

• CCTK_InterpGV() in 1-D, 2-D, and 3-D (orders 1-3) (but CartGrid3D only knows how to set up 3-D grids, so in practice only these can be tested)
• CCTK_InterpLocal() in 1-D, 2-D, and 3-D (orders 1-3).
• CCTK_InterpLocalUniform() in 1-D (orders 1-6), and 2-D and 3-D (orders 1-4); for each of these TestInterp also tests all possible derivative operations.

All the tests can be run on both single- and multi-processor systems.

At present TestInterp does this testing for each of the Cactus data types CCTK_REAL, CCTK_REAL4, CCTK_REAL8, CCTK_COMPLEX, CCTK_COMPLEX8, and CCTK_COMPLEX16.