Sometimes AlgorithmSearchProgressChartListener generates an empty chart

[agausachs]

Maybe, as Stefan comments, happens when the initial solution is already the best solution.

[jsprit]

The analysis.toolbox.AlgorithmSearchProgressChartListener.class collects in every iteration of the algorithm the best, the worst and the average solution (if there is only one solution at the end of each iteration, best=worst=average). If no solution can be found being better than the initial solution, for each iteration i best[i]=worst[i]=average[i]=initialSolution.getCosts(). When the chart-plotter scales its plot then the yAxis range is determined by minValue of all worst solutions and the maxValue of all best solutions. Since all values are equal, range.minValue = range.maxValue and thus the range is empty or there is no RANGE. Therefore, analysis.toolbox.AlgorithmSearchProgressChartListener.class creates empty charts if initial solution is already the "best" solution.

Fixed it by defining a yAxis.range if range.maxValue = range.minValue.