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scipy.stats.describe

scipy.stats.describe(a, axis=0, ddof=1, bias=True, nan_policy='propagate')[source]

Computes several descriptive statistics of the passed array.

Parameters:

a : array_like

Input data.

axis : int or None, optional

Axis along which statistics are calculated. Default is 0. If None, compute over the whole array a.

ddof : int, optional

Delta degrees of freedom (only for variance). Default is 1.

bias : bool, optional

If False, then the skewness and kurtosis calculations are corrected for statistical bias.

nan_policy : {‘propagate’, ‘raise’, ‘omit’}, optional

Defines how to handle when input contains nan. ‘propagate’ returns nan, ‘raise’ throws an error, ‘omit’ performs the calculations ignoring nan values. Default is ‘propagate’.

Returns:

nobs : int

Number of observations (length of data along axis).

minmax: tuple of ndarrays or floats

Minimum and maximum value of data array.

mean : ndarray or float

Arithmetic mean of data along axis.

variance : ndarray or float

Unbiased variance of the data along axis, denominator is number of observations minus one.

skewness : ndarray or float

Skewness, based on moment calculations with denominator equal to the number of observations, i.e. no degrees of freedom correction.

kurtosis : ndarray or float

Kurtosis (Fisher). The kurtosis is normalized so that it is zero for the normal distribution. No degrees of freedom are used.

See also

skew, kurtosis

Examples

>>> from scipy import stats
>>> a = np.arange(10)
>>> stats.describe(a)
DescribeResult(nobs=10, minmax=(0, 9), mean=4.5, variance=9.1666666666666661,
               skewness=0.0, kurtosis=-1.2242424242424244)
>>> b = [[1, 2], [3, 4]]
>>> stats.describe(b)
DescribeResult(nobs=2, minmax=(array([1, 2]), array([3, 4])),
               mean=array([ 2., 3.]), variance=array([ 2., 2.]),
               skewness=array([ 0., 0.]), kurtosis=array([-2., -2.]))