min/max for axis

[pbiebricher]

Expected Behavior

I want mirror the y-axis. My solution is to grab min and max with the ticks callback of the left y-axis and write it to the config of the right y-axis. Ths works fine with 2.9.4, but with 3.0.0-beta.10 both axis are not always syncron.

Current Behavior

It seems that min and max are not properly taken into account in the auto-fit behaviour.

Possible Solution

Steps to Reproduce

Take the examples, play with bottom Randomize Data and compare both y-axis.
https://codepen.io/pen/YzpNryM with version 2.9.4 always syncron
https://codepen.io/pen/gOLgGrO with version 3.0.0-beta.10 not always syncron

Context

Environment

• Chart.js version: 3.0.0-beta.10
• Browser name and version: Edge-dev 90.0.789.1, Firefox 85.0.2
• Link to your project:

[LeeLenaleee]

It seems to be screen dependant. On my 1080p screen it works fine, but on my 720p screen it will show the min and max, all ticks in between get grouped in the middle

[pbiebricher]

Wow, thanks for your fast response. Yes, but have you randomize the data until they go from -80 to 100 or -100 to 80. When the range changes the axis are most asyncron. Gesendet von Mail für Windows 10 Von: LeeLenaleee Gesendet: Samstag, 13. Februar 2021 15:13 An: chartjs/Chart.js Cc: pbiebricher; Author Betreff: Re: [chartjs/Chart.js] min/max for axis (#8418) It seems to be screen dependant. On my 1080p screen it works fine, but on my 720p screen it will show the min and max, all ticks in between get grouped in the middle — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or unsubscribe.

[etimberg]

I had to run a few times to make it appear. I'm not sure the best solution, but it's likely due to some caching that happens during the scale building. One idea to consider would be pre-computing the data min/max and setting those to suggestedMin and suggestedMax on the 2nd axis. That should cause the two axes to generate identical ticks.

[etimberg]

I got a working version using afterDataLimits on the left axis, but it requires re-initializing the right axis (to parse the changed options). @kurkle do you think this will get better after #8374?

https://codepen.io/etimberg/pen/oNYBoYb?editors=1000

[pbiebricher]

Hi Evert, it looks very good. I will try it in my application, which needs some time. Is chart.scales.yRight.init official or an internal function? Gesendet von Mail für Windows 10 Von: Evert Timberg Gesendet: Samstag, 13. Februar 2021 15:51 An: chartjs/Chart.js Cc: pbiebricher; Author Betreff: Re: [chartjs/Chart.js] min/max for axis (#8418) I got a working version using afterDataLimits on the left axis, but it requires re-initializing the right axis (to parse the changed options). @kurkle do you think this will get better after #8374? https://codepen.io/etimberg/pen/oNYBoYb?editors=1000 — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or unsubscribe.

[etimberg]

It's public and defined in the typescript types. I don't think we ever intended it to be called externally since it was made public for new axis types to be created. It's probably safe to call on your own since it just parses out the options passed in and stores some values.

[pbiebricher]

It’s working. Many thanks. Now I am prepared for version 3.x. Gesendet von Mail für Windows 10 Von: Evert Timberg Gesendet: Samstag, 13. Februar 2021 16:06 An: chartjs/Chart.js Cc: pbiebricher; Author Betreff: Re: [chartjs/Chart.js] min/max for axis (#8418) It's public and defined in the typescript types. I don't think we ever intended it to be called externally since it was made public for new axis types to be created. It's probably safe to call on your own since it just parses out the options passed in and stores some values. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or unsubscribe.