Flatten a list of list of paired datasets into a list of paired datasets

Sometimes you find yourself with a list:list:paired, i.e. a collection of collection of paired end data, and you really want a list:paired, a flatter collection of paired end data. This is easy to resolve with Apply rules Tool: APPLY_RULES :

1. Open Apply rules Tool: APPLY_RULES
2. Select your collection
3. Click Edit

You’ll now be in the Apply rules editing interface. There are three columns (if it’s a list:list:paired)

1. The outermost list identifier(s)
2. The next list identifier(s)
3. The paired-end indicator

Flattening this top level list, so it’s just a list:paired requires a few changes:

1. From Column menu select Concatenate Columns
   • “From Column”: A
   • “From Column”: B This creates a column with the top list identifier, and the inner list identifier, which will be our new list identifier for the flattened list.
2. From Rules menu select Add / Modify Column Definitions
   • Click Add Definition button and select Paired-end Indicator
     • “Paired-end Indicator”: C
   • Click Add Definition button and select List Identifier(s)
     • “List Identifier(s)”: D
   • Click Apply
3. Click Save
4. Click Execute

The tool will execute and reshape your list, congratulations!

Still have questions?

Want to embed this snippet (FAQ) in your GTN Tutorial?

{% snippet  topics/galaxy-interface/faqs/flatten-list-list-paired-to-list-paired.md %}