DataFrame.astype('category') duplicates column

[scidam]

the Dtaframe.pivot_table does not work correctly

Was trying to reproduce, but couldn't find the error:

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import pandas as pd data = pd.DataFrame({'x': pd.np.random.randint(0,100,1000), 'y': pd.np.random.choice(['a', 'b', 'c'], 1000)}) pd.pivot_table(data, aggfunc=pd.np.sum, values='x', columns=['y'])

Output:
y      a      b      c
x  16924  16650  16377

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# change column type data.y = data.y.astype('category') pd.pivot_table(data, aggfunc=pd.np.sum, values='x', columns=['y'])

# the result is the same...

Output:
y      a      b      c
x  16924  16650  16377