def parseArgs(args):
    """
    Parse command line arguments. Interpret strings containing ":"
    as setting global parameters.
    """
    gp = [x for x in args if     ":" in x]
    pf = [x for x in args if not ":" in x]
    if len(pf)!= 1:
        raise Exception("{} parameter files specified, require exactly 1, exiting".format(len(pf)))
    gdict = {}
    for g in gp:
        k, v = g.split(":")
        gdict[k] = float(v)
    return pf[0], gdict