Creating a time modified trend with RRDtool

[winamp]

Hi all,

I'm new to this forum and have a question about the built-in RRDtool.

I want to create a forecast of power generation and store it with RRDtool as new trend, so it's possible to show the measured power generation and the forecast in the vizualisation with multiple trends. The two trends should display as consecutive line for one day, so that the forecast trend starts at the last value of the measured power generation and ends at 24:00.

My question is, if it's possible to create a new trend with the built-in RRDtools and add it to an existing trend vizualisation via multiple trends?
If so, I would need the directory where to create and store the trend on my homeLYnk.

Thank you.

[Erwin van der Zwart]

Hi,

You can’t write to a trend yourself, but what you can do is create a dummy object an create a trend on this dummy point, then create a scheduled script and run it on the same time/resolution as your history trend.

Fetch data from your history trend and calculate the forcasted value at that moment and write this value to the dummy object, this will create a forcast trend.

BR,

Erwin

[winamp]

Unfortunately this doesn't solve my problem, because I dont need only the forcasted value at the moment, but for the rest of the day visualized as trend like in my example below.

I'm new to RRDtools and found in this thread (https://forum.logicmachine.net/showthrea...ight=trend) that "The built-in RRDtool does not have the graph option, it can only be used to store/retrieve data." So my thought was if I store the forecasted values with times in the same path like the other trends they would show up automatically. But if that is not possible I'm searching for another way to do it.

The user baggins in the same thread solved his problem, as far as I know, by exporting the data to a server where the graph is created. Is there a way to bypass the solution with a seperate server?

[admin]

This feature is not supported. If you want to export your data you can create a scheduled script that will send values each X minutes via HTTP request or any other method.