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I copied all the source code that are related to the calendar heatmap. I was able to display the chart, but all the cell colors are the same even though they have different values.
To Reproduce
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Take a look at this StackBlitz: https://stackblitz.com/edit/angular-642xtv
Expected behavior
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Demo
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Take a look at this StackBlitz: https://stackblitz.com/edit/angular-642xtv
ngx-charts version
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12.0.1
Additional context
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Your [max] input on the heatmap component is set to 50,000, while the max value in your data is 12. This is why all the colors you get are from the very beginning of your color scale, and they all end up similar.
If you change the max input to the maximum value of your data, your colors will span the full range of the color scale. Example:
https://stackblitz.com/edit/angular-il9lf4?file=src/app/app.component.ts

Most helpful comment
Your
[max]input on the heatmap component is set to 50,000, while the max value in your data is 12. This is why all the colors you get are from the very beginning of your color scale, and they all end up similar.If you change the
maxinput to the maximum value of your data, your colors will span the full range of the color scale. Example:https://stackblitz.com/edit/angular-il9lf4?file=src/app/app.component.ts