Hey Choisai,
The Charts can't take random x values as you are providing.. Or let me put it this way, you can't specify the x values explicitely for the chart. You can specify the 'dt' and intial value though.. So for your application, you can try using an XY graph where you can build the X and Y values into a cluster (use bundle function) and then wire it to the XY graph and you will see the expected x axis values.
regards,
Nitzz
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