def removeBelowValue(requestContext, seriesList, n):
    """
    Removes data below the given threshold from the series or list of series
    provided. Values below this threshold are assigned a value of None.
    """
    for s in seriesList:
        s.name = 'removeBelowValue(%s, %g)' % (s.name, n)
        s.pathExpression = s.name
        for index, val in enumerate(s):
            if val is None:
                continue
            if val < n:
                s[index] = None
    return seriesList
