Internal utilities
==================

Data wrangling
--------------

.. autofunction:: yli.utils.as_2groups
	
.. autofunction:: yli.utils.as_numeric

.. autofunction:: yli.utils.convert_pandas_nullable

*p* values
----------

.. autofunction:: yli.utils.fmt_p

.. autoclass:: yli.utils.PValueStyle
	
	.. attribute:: VALUE_ONLY
		
		Display only the *p* value (e.g. ``0.08``, ``<0.001*``)
		
		This is an alias for specifying no flags.
	
	.. attribute:: RELATION
		
		Force displaying a relational operator before the *p* value (e.g. ``= 0.08``, ``< 0.001*``)
	
	.. attribute:: TABULAR
		
		Pad with spaces to ensure decimal points align (incompatible with :attr:`RELATION`)
	
	.. attribute:: HTML
		
		Format as HTML (e.g. escape ``<``)

Formula manipulation
--------------------

.. autofunction:: yli.utils.cols_for_formula

.. autofunction:: yli.utils.formula_factor_ref_category

.. autofunction:: yli.utils.parse_patsy_term

Library style
-------------

For API nomenclature, the following guidelines are used:

* Prefer to call a test by its specific name (e.g. *anova* rather than *ftest* where applicable), unless most commonly known only by the distribution of the test statistic (e.g. *chi2*, *ttest*).

..

* A test/statistic is not referred to by both a distribution and specific name (e.g. *mannwhitney* rather than *mannwhitneyu*), unless required for disambiguation (e.g. *pearsonr* to distinguish the Pearson *χ*:sup:`2` test).

..

* The word "test" is omitted (e.g. *chi2* rather than *chi2test*), unless the name would otherwise be a single letter (e.g. *ttest*, *ftest*), or unless required for disambiguation (e.g. *LikelihoodRatioTestResult* to distinguish from the unrelated meaning of "likelihood ratio" in epidemiology).

..

* Underscores are usually omitted from the names of specific tests, test families and statistics (e.g. *ttest*, *oddsratio*, *pearsonr*, *pvalue*), but are used to separate these from other components (e.g. *ttest_ind*, *anova_oneway*, *lrtest_null*). There are a few exceptions (e.g. *rank_biserial*, *pseudo_rsquared*, *f_statistic*).

..

* The result class for a test has the same naming convention as the test function (e.g. *TTestResult* for *ttest_ind*), with abbreviations spelled out (e.g. *PearsonChiSquaredResult*, *LikelihoodRatioTestResult*); unless the result class is generic among several tests (e.g. *FTestResult* for *anova_oneway* and *RegressionResult.ftest*), or unless required for disambiguation (e.g. *PearsonChiSquaredResult* for *chi2*, as there are other *χ*:sup:`2` tests).