UniformOnePositionManipulator throws Exception if only a single value is allowed

[HeuristicLab-Trac-Bot]

Issue migrated from trac ticket # 3148

component: Encodings.IntegerVectorEncoding | priority: medium

2022-03-10 13:45:20: @NimZwei created the issue

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If the bounds for an UniformOnePositionManipulator limits the value range to a single, admissible value, an Exception is thrown.

This is caused in lines 94-95 in UniformOnePositionManipulator.cs, that were introduced in r8790:

max = FloorFeasible(min, max, step, max - 1);
vector[index] = RoundFeasible(min, max, step, random.Next(min, max));

For instance, the bounds [0, 1[ allowing only allow 0 as value, causes min and max to be 0, causing an exception when calling random.Next(min, max).

I guess, the min == max check in line 88 could be used after adapting the upper bound.