Automatically export graphs for all the time series in a given data.frame, column by column, every X data points

[technocrat]

@SimoneA

asking something that is not appropriate

Not at all!

How to run a command for each group in a column of a datframe?

Perhaps not so hard as I thought last night. Modify myfunction to open a device, run the logic to create the plots, save the file and then close the device. Test it on a single list element. If it works, then modify my_function to assemble the object name with the tiff extension.

See this recent thread. Basically, the approach is to prepare a code snippet to do a single plot, convert that code into a function and then map that function to list Pz1 ... Pz_n as arguments to the function.

Can you repost with a reprex? See the FAQ: How to do a minimal reproducible example reprex for beginners. We can help composing the function from the example, if needed, and then the mapping function.