suzerain: #3094 precompute growth rate amplitude values for spatiotemporal consistent model

git-svn-id: https://svn.ices.utexas.edu/repos/pecos/suzerain/trunk@44539 0bd85f0b-c151-43b9-a1e9-27231104551f
suzerain: improve error reporting

I believe that without double expansion all of these
would have indicated the exact same line number.

git-svn-id: https://svn.ices.utexas.edu/repos/pecos/suzerain/trunk@44541 0bd85f0b-c151-43b9-a1e9-27231104551f
suzerain: repair degenerate NaN case

See comments inline for the concern and fix details.

git-svn-id: https://svn.ices.utexas.edu/repos/pecos/suzerain/trunk@44542 0bd85f0b-c151-43b9-a1e9-27231104551f
suzerain: defend against *res going NaN

Prior commit should now save us when *res is initially NaN,
from which we should recover gracefully by spitting out NaN solution.

This commit defends against suddenly producing a NaN residual
during the iterative refinement process by balking.  That issue
like represents invalid user input or buggy behavior on our part.

The "Are we experiencing slow convergence" checks are already
sufficiently complicated that I want to eagerly rule out
encountering NaN partway through the refinement process.
Hence the location of the new logic.

git-svn-id: https://svn.ices.utexas.edu/repos/pecos/suzerain/trunk@44543 0bd85f0b-c151-43b9-a1e9-27231104551f