Sub-Totals and grouping/sorting by multiple keys

Maybe I am missing something obvious but can not find it yet. What I am trying to do is get (sub) totals for pipe lengths. In my project I have several types of pipe (e.g. Copper, Stainless Steel). For both types I have different diameters (e.g. 10, 20 mm).

What I want is the total length for each of the different pipes (i.e. Copper 10 mm, Copper 20 mm, Stainless Steel 10 mm and Stainless Steel 20 mm).

For the moment I only can manage to get the sub-totals for the pipe types, but not separated out by diameter.

What can I do to get if further separated by diameter?

Sub-Totals 2

Louis, Does this achieve what you want.

Tim,

Exactly what I need. Good solution to group the “keys” in a combined string. I like the SortListOfLists.

The only node I had to change was List.ChopByLengths. It is dropped from the Clockwork package (0.9) and can be replaced by the List.Chop from the Core functions.

 

Thanks for your help.