pandas.DataFrame.insert#

DataFrame.insert(loc,column,value,allow_duplicates=<no_default>)[source]#

Insert column into DataFrame at specified location.

Raises a ValueError ifcolumn is already contained in the DataFrame,unlessallow_duplicates is set to True.

Parameters:

locint

Insertion index. Must verify 0 <= loc <= len(columns).

columnstr, number, or hashable object

Label of the inserted column.

valueScalar, Series, or array-like

Content of the inserted column.

allow_duplicatesbool, optional, default lib.no_default

Allow duplicate column labels to be created.

See also

Index.insert

Insert new item by index.

Examples

>>>df=pd.DataFrame({'col1':[1,2],'col2':[3,4]})>>>df   col1  col20     1     31     2     4>>>df.insert(1,"newcol",[99,99])>>>df   col1  newcol  col20     1      99     31     2      99     4>>>df.insert(0,"col1",[100,100],allow_duplicates=True)>>>df   col1  col1  newcol  col20   100     1      99     31   100     2      99     4

Notice that pandas uses index alignment in case ofvalue from typeSeries:

>>>df.insert(0,"col0",pd.Series([5,6],index=[1,2]))>>>df   col0  col1  col1  newcol  col20   NaN   100     1      99     31   5.0   100     2      99     4