#   scipy-yli: Helpful SciPy utilities and recipes
#   Copyright © 2022–2023  Lee Yingtong Li (RunasSudo)
#
#   This program is free software: you can redistribute it and/or modify
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#   the Free Software Foundation, either version 3 of the License, or
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#
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from pytest import approx

import numpy as np
import pandas as pd

import yli

def test_ttest_ind_ol6_1():
	"""Compare yli.ttest_ind for Ott & Longnecker (2016) example 6.1"""
	
	df = pd.DataFrame({
		'Type': ['Fresh'] * 10 + ['Stored'] * 10,
		'Potency': [10.2, 10.5, 10.3, 10.8, 9.8, 10.6, 10.7, 10.2, 10.0, 10.6, 9.8, 9.6, 10.1, 10.2, 10.1, 9.7, 9.5, 9.6, 9.8, 9.9]
	})
	
	result = yli.ttest_ind(df, 'Potency', 'Type')
	
	t_expected = 0.54/(0.285*np.sqrt(1/10+1/10))
	
	assert result.statistic == approx(t_expected, abs=0.01)
	assert result.dof == 18
	assert result.delta.point == approx(0.54, abs=0.01)
	assert result.delta.ci_lower == approx(0.272, abs=0.01)
	assert result.delta.ci_upper == approx(0.808, abs=0.01)
	
	expected_summary = '''Type            Fresh       Stored
Potency                           
μ (SD)   10.37 (0.32)  9.83 (0.24)

t(18) = 4.24; p < 0.001*
Δμ (95% CI) = 0.54 (0.27–0.81), Fresh > Stored'''
	
	assert result.summary() == expected_summary
	assert result._repr_html_() == '<div>\n<style scoped>\n    .dataframe tbody tr th:only-of-type {\n        vertical-align: middle;\n    }\n\n    .dataframe tbody tr th {\n        vertical-align: top;\n    }\n\n    .dataframe thead th {\n        text-align: right;\n    }\n</style>\n<table border="1" class="dataframe">\n  <thead>\n    <tr style="text-align: right;">\n      <th>Type</th>\n      <th>Fresh</th>\n      <th>Stored</th>\n    </tr>\n    <tr>\n      <th>Potency</th>\n      <th></th>\n      <th></th>\n    </tr>\n  </thead>\n  <tbody>\n    <tr>\n      <th><i>μ</i> (SD)</th>\n      <td>10.37 (0.32)</td>\n      <td>9.83 (0.24)</td>\n    </tr>\n  </tbody>\n</table>\n</div><br><i>t</i>(18) = 4.24; <i>p</i> &lt; 0.001*<br>Δ<i>μ</i> (95% CI) = 0.54 (0.27–0.81), Fresh > Stored'