Nicolas Tancogne-Dejean requested to merge fix_bicgstab into develop Feb 03, 2021

Description

Fix the exit conditions of the BiCGStab algorithm. Only an exact comparison to zero is needed here.

News snippet

Fix for the BiCGStab linear solver.

Checklist

I have checked that my code follows the Octopus coding standards
I have added tests for all the new features added in this request.