def _sf(self, k, M, n, N):
<EOL>res = []<EOL>for quant, tot, good, draw in zip(k, M, n, N):<EOL><INDENT>k2 = np.arange(quant + <NUM_LIT:1>, draw + <NUM_LIT:1>)<EOL>res.append(np.sum(self._pmf(k2, tot, good, draw)))<EOL><DEDENT>return np.asarray(res)<EOL>
More precise calculation, 1 - cdf doesn't cut it.