- dont know which file to use as it is only allowed one file*
A collection is a folder of similar files, so tool forms are able to handle those as a sort of “single file” but will run the manipulation on all files inside that same folder.
For this tool, those files are being sorted to modify the ordering inside the folder. This manipulation can help when using tools that accept multiple collections, and are “matching up” files between collections. For example: Collection A, Dataset 1 needs Collection B, Dataset 1 for some processing.
If your data is not in a collection yet, back up in the tutorial to the steps where those are created from the loaded starting files. Why? It is very difficult to attempt to pair up files directly if they are “loose” in the history as individual files. Not impossible, but much more difficult than creating and using collection folders.
Hopefully this helps!