def get_parameters(results):
    """
    Get an shorter array out of your result array, containing just the
    parameters of your model.

    :results: Expects an numpy array which should have indices beginning with "par"
    :type: array

    :return: Array containing just the columns beginnning with the indice "par"
    :rtype: array
    """
    fields=[word for word in results.dtype.names if word.startswith('par')]
    results = results[fields]
    return results