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Select all rows that contain the first x unique values in another column in Pandas [Python]

selected =df['col2'].unique().iloc[1:5]
apples = df[df['col2'].isin([selected])]
print(df)

Here is my pseudocode for what I'm trying to accomplish. I just want to get the first five unique values in column 2, and then subset the whole dataframe based on those values. I get this error on the first line:

AttributeError: 'numpy.ndarray' object has no attribute 'iloc'
question from:https://stackoverflow.com/questions/66061546/select-all-rows-that-contain-the-first-x-unique-values-in-another-column-in-pand

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1 Answer

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The only issue is your array slicing

df = pd.DataFrame({"col2":np.random.randint(1,50,100)})
df[df["col2"].isin(df['col2'].unique()[:5])]

output

col2
0 3
1 13
2 1
3 27
4 4
9 1
20 13
27 1
31 4
35 4
42 13
43 27
48 3
59 4
60 4
67 4
90 3
95 4
96 4
98 13

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