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QST: why changing dataframe values impacts the array that the dataframe was created from?
See original GitHub issue-
I have searched the [pandas] tag on StackOverflow for similar questions.
-
I have asked my usage related question on StackOverflow.
Question about pandas
>>> import numpy as np
>>> import pandas as pd
>>> mat = np.array([[1,2], [2,3]])
>>> mat
array([[1, 2],
[2, 3]])
>>> df = pd.DataFrame(mat)
>>> df.iloc[0,1] = 4
>>> mat
array([[1, 4],
[2, 3]])
Why the value in the original mat is also changed? I am not sure if this is a bug or Pandas’ way of doing things. I found it to be very confusing.
Issue Analytics
- State:
- Created 2 years ago
- Comments:5 (5 by maintainers)
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closing - democracy seems to have identified this as a non-issue, but rather an educational question for which an answer was given
@Varun270 the relevant code will be in
pandas.core.frameorpandas.core.generic. However, it seems to me there is no issue to be resolved here.