Add helper function for making dtype ordinal (ordered category)

yli/__init__.py

@@ -21,6 +21,7 @@ from .distributions import beta_oddsratio, beta_ratio, hdi, transformed_dist
 from .io import pickle_read_compressed, pickle_read_encrypted, pickle_write_compressed, pickle_write_encrypted
 from .regress import OrdinalLogit, PenalisedLogit, logit_then_regress, regress, vif
 from .sig_tests import anova_oneway, auto_univariable, chi2, mannwhitney, pearsonr, spearman, ttest_ind
+from .utils import as_ordinal
 
 def reload_me():
 	import importlib

yli/utils.py

@@ -135,6 +135,22 @@ def as_numeric(data):
 	
 	return data.astype('float64'), None
 
+def as_ordinal(data):
+	"""
+	Convert the data to an ordered category dtype
+	
+	:param data: Data to convert
+	:type df: Series
+	
+	:rtype: Series
+	"""
+	
+	if data.dtype == 'category':
+		if data.cat.ordered:
+			return data
+		return data.cat.as_ordered()
+	return data.astype(pd.CategoricalDtype(ordered=True))
+
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 # Formatting