# Time Series Chart - Auto-Scaling when Selecting Specific Key

**URL:** <https://forum.inductiveautomation.com/t/time-series-chart-auto-scaling-when-selecting-specific-key/31959>\
**Category:** Ignition\
**Tags:** perspective\
**Created:** [February 5, 2020, 5:26pm UTC](https://forum.inductiveautomation.com/t/time-series-chart-auto-scaling-when-selecting-specific-key/31959 "2020-02-05T17:26:58Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![jaspinall](https://avatars.discourse-cdn.com/v4/letter/j/a587f6/32.png) [@jaspinall](https://forum.inductiveautomation.com/u/jaspinall)\
**Post date:** [February 5, 2020, 5:26pm UTC](https://forum.inductiveautomation.com/t/time-series-chart-auto-scaling-when-selecting-specific-key/31959/1 "2020-02-05T17:26:58Z")

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Hello There,

I have three points being trended on my time-series chart (1. Thermocouple #1 2. Thermocouple #2 and 3. Thermocouple #3 and I am wondering if the following is possible:

Currently when the user clicks on the “Thermocouple #1” legend icon for example it hides all other items being trended and focuses in on Thermocouple #1. What I am wondering is, is it possible to also make it temporarily auto-scale the trending Y axis to that of min/max of Thermocouple #1 when it is selected?

Thank You

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**Author:** ![jball](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/jball/32/11128_2.png) [@jball](https://forum.inductiveautomation.com/u/jball)\
**Post date:** [February 5, 2020, 8:49pm UTC](https://forum.inductiveautomation.com/t/time-series-chart-auto-scaling-when-selecting-specific-key/31959/2 "2020-02-05T20:49:02Z")

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Hi @jaspinall, the “zoom while selected” behavior that you’re requesting is an interesting idea. I can certainly create a feature request and see where it goes.

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**Author:** ![jaspinall](https://avatars.discourse-cdn.com/v4/letter/j/a587f6/32.png) [@jaspinall](https://forum.inductiveautomation.com/u/jaspinall)\
**Post date:** [February 5, 2020, 9:02pm UTC](https://forum.inductiveautomation.com/t/time-series-chart-auto-scaling-when-selecting-specific-key/31959/3 "2020-02-05T21:02:30Z")

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Thanks for the reply jball. That would be appreciated.

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**Author:** ![andytimc](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/andytimc/32/11938_2.png) [@andytimc](https://forum.inductiveautomation.com/u/andytimc)\
**Post date:** [March 25, 2020, 1:24pm UTC](https://forum.inductiveautomation.com/t/time-series-chart-auto-scaling-when-selecting-specific-key/31959/4 "2020-03-25T13:24:05Z")

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@jaspinall since autorange isn’t built in I used a little workaround using an expression. I bound the the Plot-\>Axes-\>Max value to an expression which uses the max() function to return the max value in the trend series dataset and multiplies it by 110% to add a little bit to the top of the chart. This is working the way I need it to.

```auto
round(max({this.props.series[0].data},1)*1.1,0)

```

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**Author:** ![jaspinall](https://avatars.discourse-cdn.com/v4/letter/j/a587f6/32.png) [@jaspinall](https://forum.inductiveautomation.com/u/jaspinall)\
**Post date:** [March 25, 2020, 3:18pm UTC](https://forum.inductiveautomation.com/t/time-series-chart-auto-scaling-when-selecting-specific-key/31959/5 "2020-03-25T15:18:48Z")

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Very cool @andytimc - thanks for sharing