Where's the endless loop?

[deanhystad]

Your code was taking a long time when you added bars to the chart one at a time. Now you plot all the bars at once, just like I am doing. Looping to group the data will be slower than using the dataset functions, but the difference is so minor when compared to the time it takes to plot that it is lost in the noise. I expect looping though your data takes less than a millisecond and using the dataset function might be 100 times faster. No discernable difference. If you were doing analysis on millions of points of data you would notice a difference.