visualmap pieces在只有开区间设置时报错Cannot read property 'coord' of undefined

[facingcheer]

Version

5.0.2

Steps to reproduce

正常：http://jsfiddle.net/facingcheer/mt7re6xg/1/
异常： http://jsfiddle.net/facingcheer/va64jt2e/5/
经过测试如果所有的pieces都是开区间 在计算stops的时候就会异常

What is expected?

在所有pieces都设置为开区间的时候正常渲染图表

What is actually happening?

在所有pieces都设置为开区间的时候无法渲染

[echarts-bot]

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[echarts-bot]

@facingcheer It seems you are not using English, I've helped translate the content automatically. To make your issue understood by more people, we'd like to suggest using English next time. 🤗

TRANSLATED

TITLE

Visualmap pieces report an error Cannot read property'coord' of undefined when only the open interval is set

BODY

Version

5.0.2

Steps to reproduce

Normal: http://jsfiddle.net/facingcheer/mt7re6xg/1/
Exception: http://jsfiddle.net/facingcheer/va64jt2e/5/
Tested if allpieces are open intervals will be abnormal when calculating stops

What is expected?

The chart is rendered normally when allpieces are set to open intervals

What is actually happening?

Rendering is not possible when allpieces are set to open intervals

[susiwen8]

Related to #12374

[github-actions]

This issue has been automatically marked as stale because it did not have recent activity. It will be closed in 7 days if no further activity occurs. If you wish not to mark it as stale, please leave a comment in this issue.

[github-actions]

This issue has been automatically closed because it did not have recent activity. If this remains to be a problem with the latest version of Apache ECharts, please open a new issue and link this to it. Thanks!