I have a few questions about trends that I hope someone can provide some input to. I’m trying to make Ignition work more like some of the larger historian products on the market, so if you’ve used one of those, I think you’ll know what I mean. These are a few of the items holding me back from using Ignition for these ad-hod needs, and have me entertaining a historian or other custom developed product.
(For those of you at IA, I’ve already emailed a document to my rep for a more formal response)
First Question:
A lot of historians have the ability to make a note on a point in time through the trend interface. I see that there is a module to do something similar in Ignition. marketplace.inductiveautomation. … oduleId=86
I have a need to mark a time range on a trend graph and make some notes about that time period. Either for a single tag or a group of tags. Has this been done? Can anyone speak to the complexity of doing this?
Second Question:
I know the new version has CTG build in, essentially. What about exposing the ability to add calculations to an ad-hoc graph? For example, allow the end-user to create a trend line that comprises of an expression that may involve other tags.
Third Question:
What about overlapping time trends? If I want to see 5 years of the same tag overlapping. I’m sure I could figure out a way to do this from the designer, but is there a way it could be ad-hoc from the user side?
[quote=“tomt”]A lot of historians have the ability to make a note on a point in time through the trend interface. I see that there is a module to do something similar in Ignition. marketplace.inductiveautomation. … oduleId=86[/quote]This would be mine. [quote=“tomt”]I have a need to mark a time range on a trend graph and make some notes about that time period. Either for a single tag or a group of tags. Has this been done? Can anyone speak to the complexity of doing this?[/quote]Another user made a similar request here. It’s on my to-do list. The key is that you need two events to represent the beginning and ending of your range. If you have a table storing your comments with the time ranges, simply unioning the table with itself can give you the behavior you want. Tieing the comments to specific tags would be another relation in the database to filter against. All of this is doable (but not simple) given a good description of the desired user interface behavior.
[quote=“tomt”]I know the new version has CTG build in, essentially. What about exposing the ability to add calculations to an ad-hoc graph? For example, allow the end-user to create a trend line that comprises of an expression that may involve other tags.[/quote]The ability to compute chart pens exists for a few functions, against single pens already on the chart. There’s no runtime UI to do this. If you are using database pens, you could predefine some calculated values in database views and make those selectable at runtime. But the runtime properties are exposed to scripting, so this could all be done. Can it support fully free-form expressions and/or multiple tags? No.
[quote=“tomt”]What about overlapping time trends? If I want to see 5 years of the same tag overlapping. I’m sure I could figure out a way to do this from the designer, but is there a way it could be ad-hoc from the user side?[/quote]Ow! That makes my head hurt.
This could be done at design-time with the Classic chart by computing data sets that have the appropriate amount of time added to their x-axis column. For the EasyChart, the only thing that comes to mind is a database view with such offsets accessed with DB pens.
HTH,
Phil
[quote=“tomt”]I have a need to mark a time 