Detailed Description

Unit tests for the Rusanov face fluxes and the geometric source, numeric/EulerFlux.h.

These five functions are header-only and take plain doubles, so each can be pinned against hand-evaluated arithmetic. That is what the Python suite cannot do: it reaches them only through hydroStep(), where a sign error in one term shows up as a wrong profile several hundred sub-cycles later, with every other row active at the same time.

What is asserted here is the SHAPE of each flux – which quantity is averaged, which is dissipated, and where r_face multiplies – because those are the distinctions NUMERICS.md sections 5.2 and 5.4 say the rows are easy to get wrong in ways that still produce a plausible answer.

Definition in file EulerFlux_test.cpp.