python - Pandas: Add multiple empty columns to DataFrame -

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this may stupid question, how add multiple empty columns dataframe list?

i can do:

df["b"] = none df["c"] = none df["d"] = none

but can't do:

df[["b", "c", "d"]] = none  keyerror: "['b' 'c' 'd'] not in index"

i'd concat using dataframe ctor:

in [23]: df = pd.dataframe(columns=['a']) df  out[23]: empty dataframe columns: [a] index: []  in [24]:     pd.concat([df,pd.dataframe(columns=list('bcd'))])  out[24]: empty dataframe columns: [a, b, c, d] index: []

so passing list containing original df, , new 1 columns wish add, return new df additional columns.


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