Tested in UPPAAL 4.1.14 (rev. 5212) With the attached simple system, the queries simulate 50 [<=1] {P.Done} simulate 50 [<=1] {P.Done} : P.Done simulate 50 [<=1] {P.Done} : wallclock >= 1 draw the expected result with only horizontal and vertical line segments in the plot. However, the queries simulate 50 [<=500] {P.Done} : P.Done simulate 50 [<=500] {P.Done} : wallclock >= 1 draw undesirables results with lots of sloped lines (some of them are vertical as expected, though). Presumably addPoint in server/modules/statmc/ProbaChecker.cpp considers too many points to be in the same "column" and skips them because the stop condition changes the effective overall plot width from 500 to 1 time unit. Changing the trace resolution in the Statistical parameters menu affects which lines in the plot become sloped and which ones that stay vertical as they were expected to.
Created attachment 257 [details] A simple system to illustrate the bug It didn't seem to keep my attachment the first time.