Optimizing a "set in a string list" to a "set as a matrix" operation
- by Eric Fournier
I have a set of strings which contain space-separated elements. I want to build a matrix which will tell me which elements were part of which strings. For example:
""
"A B C"
"D"
"B D"
Should give something like:
A B C D
1
2 1 1 1
3 1
4 1 1
Now I've got a solution, but it runs slow as molasse, and I've run out of ideas on how to…