37 lines
913 B
Python
37 lines
913 B
Python
import pandas as pd
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import numpy as np
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df = pd.read_csv('/home/pi/Documents/Code/Python/ProgrammierungUndDatenanalyse/Sonstiges/STAT2/vl2-varianz-v1.csv')
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# Dataframe
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print(df)
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# x freq
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# 0 1 9
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# 1 2 7
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# 2 3 5
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# 3 4 4
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# 4 5 2
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print(df.sum())
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# x 15
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# freq 27
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sums = df.sum()
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print(sums['freq'])
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# 27
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# Calculate Mean, respecting frequencies
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rowSum = 0
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for index, row in df.iterrows():
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rowSum = rowSum + row.x * row.freq
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mean = rowSum / sums.freq
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print("mean: ", mean)
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# Calculate Variance, respecting frequencies
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# Sample Variance: ^σ² = (1 / n - 1) * Σ(freq*(x - mean)²)
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variancePart1 = (1 / (sums.freq - 1))
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variancePart2 = 0
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for index, row in df.iterrows():
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variancePart2 = variancePart2 + (row.freq * (row.x - mean)**2)
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print(row['x'], row['freq'], variancePart2)
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variance = variancePart1 * variancePart2
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print("variance: ", variance)
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# variance: 1.703703703703704 |