Xcos solvers suggestion: add Crank-Nicolson
Reported by Paul BIGNIER
Originally assigned to Paul BIGNIER
BUG DESCRIPTION:
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The Crank_Nicolson scheme is famous and appreciated in diffusion-advection problems (for instance, the heat equation).
It would enrich the list of implicit fixed-step solvers (right now, we only have ImpRK).
Just like the 3 other fixed-step solvers, it would integrate easily in CVODE's source code.
ERROR LOG:
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HOW TO REPRODUCE THE BUG:
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OTHER INFORMATION:
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