Where:
- use_helix is an integer number
- helix_length is an integer number
- helix_target is an integer number
- use_strand is an integer number
- strand_length is an integer number
- strand_target is an integer number
autobuild secondary structure
Find secondary structure in the current map. Add to a molecule called "SecStruc", create it if needed.
Returns: the index of the new molecule.