load a pest-compatible .par file into a pandas.DataFrame

    Parameters
    ----------
    parfile : str
        pest parameter file name

    Returns
    -------
    pandas.DataFrame : pandas.DataFrame

def read_parfile(parfile):
    """load a pest-compatible .par file into a pandas.DataFrame

    Parameters
    ----------
    parfile : str
        pest parameter file name

    Returns
    -------
    pandas.DataFrame : pandas.DataFrame

    """
    assert os.path.exists(parfile), "Pst.parrep(): parfile not found: " +\
                                    str(parfile)
    f = open(parfile, 'r')
    header = f.readline()
    par_df = pd.read_csv(f, header=None,
                             names=["parnme", "parval1", "scale", "offset"],
                             sep="\s+")
    par_df.index = par_df.parnme
    return par_df