How do I manipulate or transform tag history data in a Power Chart?
Figure 1. How can I feed this with a tag history binding so that I can run a transform on the data?
I’m logging non-resetting machine cycle counters and want to present a graph that starts at y = 0 no matter what start date is selected. My idea is to subtract the start count value from every record in the dataset. I can’t figure out a way to do it.
In this related question the OP has figured out how to use a custom method but hasn’t explained how to trigger the method:
In the methode he is refering to the table as getChild so im guessing this is just triggered in a startup script on the root component or a binding in the root to the his query tag self.custom.TrendGroupPenData
I don’t think you can. The Power Chart is abstracted to just provide a tag path and it handles the rest. If you need to manipulate history data, you’ll have to use one of the other charts where you have to do the heavy lifting of providing data…not just a tag path.
Please do. I had to create one too that I am not proud of to post on the Exchange. Ideally if it could replicate the same UI/functionality as the one built-in to the Power Chart, that would be great. That one is minimalistic for mobile use.