scipy.stats.ksone¶
- scipy.stats.ksone = <scipy.stats._continuous_distns.ksone_gen object at 0x5812950>[source]¶
General Kolmogorov-Smirnov one-sided test.
As an instance of the rv_continuous class, ksone object inherits from it a collection of generic methods (see below for the full list), and completes them with details specific for this particular distribution.
Examples
>>> from scipy.stats import ksone >>> import matplotlib.pyplot as plt >>> fig, ax = plt.subplots(1, 1)
Calculate a few first moments:
>>> n = 1e+03 >>> mean, var, skew, kurt = ksone.stats(n, moments='mvsk')
Display the probability density function (pdf):
>>> x = np.linspace(ksone.ppf(0.01, n), ... ksone.ppf(0.99, n), 100) >>> ax.plot(x, ksone.pdf(x, n), ... 'r-', lw=5, alpha=0.6, label='ksone pdf')
Alternatively, the distribution object can be called (as a function) to fix the shape, location and scale parameters. This returns a “frozen” RV object holding the given parameters fixed.
Freeze the distribution and display the frozen pdf:
>>> rv = ksone(n) >>> ax.plot(x, rv.pdf(x), 'k-', lw=2, label='frozen pdf')
Check accuracy of cdf and ppf:
>>> vals = ksone.ppf([0.001, 0.5, 0.999], n) >>> np.allclose([0.001, 0.5, 0.999], ksone.cdf(vals, n)) True
Generate random numbers:
>>> r = ksone.rvs(n, size=1000)
And compare the histogram:
>>> ax.hist(r, normed=True, histtype='stepfilled', alpha=0.2) >>> ax.legend(loc='best', frameon=False) >>> plt.show()
Methods
rvs(n, loc=0, scale=1, size=1, random_state=None) Random variates. pdf(x, n, loc=0, scale=1) Probability density function. logpdf(x, n, loc=0, scale=1) Log of the probability density function. cdf(x, n, loc=0, scale=1) Cumulative density function. logcdf(x, n, loc=0, scale=1) Log of the cumulative density function. sf(x, n, loc=0, scale=1) Survival function (also defined as 1 - cdf, but sf is sometimes more accurate). logsf(x, n, loc=0, scale=1) Log of the survival function. ppf(q, n, loc=0, scale=1) Percent point function (inverse of cdf — percentiles). isf(q, n, loc=0, scale=1) Inverse survival function (inverse of sf). moment(n, n, loc=0, scale=1) Non-central moment of order n stats(n, loc=0, scale=1, moments='mv') Mean(‘m’), variance(‘v’), skew(‘s’), and/or kurtosis(‘k’). entropy(n, loc=0, scale=1) (Differential) entropy of the RV. fit(data, n, loc=0, scale=1) Parameter estimates for generic data. expect(func, args=(n,), loc=0, scale=1, lb=None, ub=None, conditional=False, **kwds) Expected value of a function (of one argument) with respect to the distribution. median(n, loc=0, scale=1) Median of the distribution. mean(n, loc=0, scale=1) Mean of the distribution. var(n, loc=0, scale=1) Variance of the distribution. std(n, loc=0, scale=1) Standard deviation of the distribution. interval(alpha, n, loc=0, scale=1) Endpoints of the range that contains alpha percent of the distribution