You are viewing a plain text version of this content. The canonical link for it is here.

Posted to commits@echarts.apache.org by GitBox <gi...@apache.org> on 2021/09/03 11:43:49 UTC

[GitHub] [echarts] lxr900 opened a new issue #15674: Use actual area measure instead of radius in Rose Chart

lxr900 opened a new issue #15674:
URL: https://github.com/apache/echarts/issues/15674

### What problem does this feature solve?
With `roseType: area` property of the `pie` type chart, sectors have their radius mapped to the data instead of the area, which is misleading not only in the graph options definition, but also as the resulting visualization.

In fact longer slices receive more emphasis than they should because of their larger area size. This disproportionately represents increases in value, leading the reader to exaggerate the differences.

Mapping the data value to the area instead of the radius would thus both make the api more consistent and the final result more accurate and effective.

### What does the proposed API look like?
Rather than an API change it's just a different calculation of the slice radius, which should be calculated using the square root of the value, instead of the value itself. I.E. if values are `[4,9,25]` using `[2,3,5]` as the radius.

Demonstration as follows.

With:

```
alpha = central angle of the slice

At = total area of the circle = pi * r^2

As = slice area = ( ( pi * r^2 ) / ( 2 * pi ) ) * alpha = r^2 * ( alpha / 2 )
```

Since alpha is equal for all slices, slice areas will be proportional to the square of the radius. Thus, to obtain areas with the same proportion of the datapoints, the actual radiuses should be proportional to the square root of the data points.

--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: commits-unsubscribe@echarts.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org

---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscribe@echarts.apache.org
For additional commands, e-mail: commits-help@echarts.apache.org

[GitHub] [echarts] echarts-bot[bot] commented on issue #15674: Use actual area measure instead of radius in Rose Chart

Posted by GitBox <gi...@apache.org>.

echarts-bot[bot] commented on issue #15674:
URL: https://github.com/apache/echarts/issues/15674#issuecomment-912475154

Hi! We've received your issue and please be patient to get responded. 🎉
The average response time is expected to be within one day for weekdays.

In the meanwhile, please make sure that it contains **a minimum reproducible demo** and necessary **images** to illustrate. Otherwise, our committers will ask you to do so.

*A minimum reproducible demo* should contain as little data and components as possible but can still illustrate your problem. This is the best way for us to reproduce it and solve the problem faster.

You may also check out the [API](http://echarts.apache.org/api.html) and [chart option](http://echarts.apache.org/option.html) to get the answer.

If you don't get helped for a long time (over a week) or have an urgent question to ask, you may also send an email to dev@echarts.apache.org. Please attach the issue link if it's a technical question.

If you are interested in the project, you may also subscribe to our [mailing list](https://echarts.apache.org/en/maillist.html).

Have a nice day! 🍵

--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: commits-unsubscribe@echarts.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org

---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscribe@echarts.apache.org
For additional commands, e-mail: commits-help@echarts.apache.org