def quantile(self, p):
        """
        Estimated quantile of a survival distribution.

        Parameters
        ----------
        p : float
            The probability point at which the quantile
            is determined.

        Returns the estimated quantile.
        """

        # SAS uses a strict inequality here.
        ii = np.flatnonzero(self.surv_prob < p - 1)

        if len(ii) == 0:
            return np.nan

        return self.surv_times[ii[0]]
dataset/ETHPy150Open statsmodels/statsmodels/statsmodels/duration/survfunc.py/SurvfuncRight.quantile/swapped operands of `-`