w_select predicate function

predicate.py

# For use with w_select.py, part of the WESTPA west_tools package
# Thanks to Ali Sinan Saglam

def predicate(n_iter, iter_group):
    pcoord = iter_group['pcoord']
    collection = []
    # Iterate over the segments
    for iseg,seg in enumerate(pcoord):
        # seg should return the pcoord array for every timepoint.
        # If your pcoord is N dimensional, be sure to return the appropriate dimension
        # seg[timepoint,dimension]
        # Check the final timepoint for some logic; in this case, is our final pcoord timepoint
        # over 5.0?
        if seg[-1,0] > 5.0:
            collection.append(iseg)
    return collection