def _logpdf(self, x, df):
        l = np.log(2) - .5*np.log(2)*df - special.gammaln(.5*df)
        return l + special.xlogy(df-1.,x) - .5*x**2
dataset/ETHPy150Open scipy/scipy/scipy/stats/_continuous_distns.py/chi_gen._logpdf/original