def pts_to_verts(xvec, yvec):
    """
    Convert points to vertices, i.e., convert from 2 1D arrays (or list) of     x- and y-coordinates to a list-of-lists of [x,y] pairs
    """
    verts = []
    for count in range(len(xvec)):
        verts.append([xvec[count], yvec[count]])
    return verts
