When max_y or min_y is set, the chart line sometimes curves in such a way that peaks are invisible

[openjck]

Steps to reproduce

Download and open this HTML document

Actual result

Screenshot

Expected result

The chart should look something like this (achieved by removing max_y):

[openjck]

Any recommended workarounds?

[wlach]

Offhand I would suggest setting the max_y to something like 2.5 as a workaround? That seems to fix the issue for me:

https://jsfiddle.net/osz2vxom/

I agree we should do better than this though. I'd guess that the fix place for the fix is in the line chart code:

https://github.com/mozilla/metrics-graphics/blob/5538f8c97e18f2c9c01246b0d717932276a5e98b/src/js/charts/line.js

[openjck]

I'll have to try that again. When I tried it in the project where I noticed this issue, setting a higher max_y didn't seem to work. But I must have been missing something. Thanks!

[openjck]

The same happens with min_y, FWIW.