#   scipy-yli: Helpful SciPy utilities and recipes
#   Copyright © 2022  Lee Yingtong Li (RunasSudo)
#
#   This program is free software: you can redistribute it and/or modify
#   it under the terms of the GNU Affero General Public License as published by
#   the Free Software Foundation, either version 3 of the License, or
#   (at your option) any later version.
#
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#   but WITHOUT ANY WARRANTY; without even the implied warranty of
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#   GNU Affero General Public License for more details.
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from pytest import approx

import pandas as pd
import statsmodels.api as sm

import yli

def test_anova_oneway_ol8_2():
	"""Compare yli.anova_oneway for Ott & Longnecker (2016) example 8.2"""
	
	df = pd.DataFrame({
		'Method': [1]*8 + [2]*7 + [3]*9,
		'Score': [96, 79, 91, 85, 83, 91, 82, 87, 77, 76, 74, 73, 78, 71, 80, 66, 73, 69, 66, 77, 73, 71, 70, 74]
	})
	
	result = yli.anova_oneway(df, 'Score', 'Method')
	
	assert result.statistic == approx(545.316/18.4366, rel=0.001)
	assert result.dof1 == 2
	assert result.dof2 == 21
	assert result.pvalue < 0.001

def test_regress_ftest_ol8_2():
	"""Compare ANOVA via yli.regress for Ott & Longnecker (2016) example 8.2"""
	
	df = pd.DataFrame({
		'Method': [1]*8 + [2]*7 + [3]*9,
		'Score': [96, 79, 91, 85, 83, 91, 82, 87, 77, 76, 74, 73, 78, 71, 80, 66, 73, 69, 66, 77, 73, 71, 70, 74]
	})
	
	result = yli.regress(sm.OLS, df, 'Score', 'C(Method)').ftest()
	
	assert result.statistic == approx(545.316/18.4366, rel=0.001)
	assert result.dof1 == 2
	assert result.dof2 == 21
	assert result.pvalue < 0.001