Hello. My goal is to make a time series graph of a tag, let's say temperature in a given vessel. Ideally I'd like to display the time series for that value on top of a preferred range - for example if the temperature gets below 10 C or above 40 C I'd like to see it crossing a line on the graph, or even crossing into a shaded red area.
It's not clear in the Perspective manual what's the right way to do this: Time Series Chart. For example trends > baselines > upper and lower control limit sounds promising, but it is unclear how to set the control limits. If I try setting the baseline function to lower control limit nothing shows up on the chart.
Similarly setting markers > line to a value of 10 seems like a reasonable way to do this, but nothing shows up on the chart. Possibly it's because by default there is no "axis" to select?
The Time Series instructional video doesn't go over any of this, are there any other videos that are relevant? Perhaps for other chart types?
The trends on the Time Series Chart are derived values from your existing data. These are a handy way to easily show things like min, max, avg, etc. The upper and lower control limits are also derived from your data and are common ways of portraying statistics (and don't sound like what you're looking for).
There are two approaches I would take here:
Add constant Values to the Objects in data to portray min/max values. This will plot additional lines with your data to represent your min/max values.
Use an XY Chart. With an XY Chart you can plot multiple data sources onto a single chart. You can even use the same axes for the different data sources. This approach would keep your data separate from your min and max values while plotting them on the same chart. You can even choose a fill option for a line to represent a shaded area.
I would go with approach #2 as it offers the most flexibility and separates your data from the hard coded values. You could even have two points for your min/max values and derive the x (time) values from your original data source, creating a line across the chart.
Thanks, I will look into these! I also found a the Sparkline graph, which is a sort of minimalist graph where you can add desired ranges. Might be a possibility.
That could be OK but it relies on even time intervals on the data otherwise it's not going to be to "scale".