mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-10-17 20:28:43 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 9

bpo-36546: Add more tests and expand docs (#13406)

Browse source
This commit is contained in:
Raymond Hettinger 2019-05-18 10:18:29 -07:00 • committed by GitHub
parent 73934b9da0
commit e917f2ed9a
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
2 changed files with 48 additions and 21 deletions
Download patch file Download diff file Expand all files Collapse all files

31
Doc/library/statistics.rst
View file

@ -511,22 +511,33 @@ However, for reading convenience, most of the examples show sorted sequences.
is not least 1.
The *dist* can be any iterable containing sample data or it can be an
instance of a class that defines an :meth:`~inv_cdf` method.
instance of a class that defines an :meth:`~inv_cdf` method. For meaningful
results, the number of data points in *dist* should be larger than *n*.
Raises :exc:`StatisticsError` if there are not at least two data points.
For sample data, the cut points are linearly interpolated from the
two nearest data points. For example, if a cut point falls one-third
of the distance between two sample values, ``100`` and ``112``, the
cut-point will evaluate to ``104``. Other selection methods may be
offered in the future (for example choose ``100`` as the nearest
value or compute ``106`` as the midpoint). This might matter if
there are too few samples for a given number of cut points.
cut-point will evaluate to ``104``.
If *method* is set to *inclusive*, *dist* is treated as population data.
The minimum value is treated as the 0th percentile and the maximum
value is treated as the 100th percentile. If *dist* is an instance of
a class that defines an :meth:`~inv_cdf` method, setting *method*
has no effect.
The *method* for computing quantiles can be varied depending on
whether the data in *dist* includes or excludes the lowest and
highest possible values from the population.
The default *method* is "exclusive" and is used for data sampled from
a population that can have more extreme values than found in the
samples. The portion of the population falling below the *i-th* of
*m* data points is computed as ``i / (m + 1)``.
Setting the *method* to "inclusive" is used for describing population
data or for samples that include the extreme points. The minimum
value in *dist* is treated as the 0th percentile and the maximum
value is treated as the 100th percentile. The portion of the
population falling below the *i-th* of *m* data points is computed as
``(i - 1) / (m - 1)``.
If *dist* is an instance of a class that defines an
:meth:`~inv_cdf` method, setting *method* has no effect.
.. doctest::