maxIterations depends on minTimestep
In the constructor of CalculationController, eps is used to instantiate itmax as an increased value from time.maxIterations. However, eps is instantiated from dtmin, which can cause trouble if the latter is set too high. Specifically, itmax was decreased below itmin, which caused the solver to fail.
Solution: Use rounding in calcIterations, save iterations as integers, remove eps from itmax constructor.
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