Converting a column within pandas dataframe from int to string

Question

I have a dataframe in pandas with mixed int and str data columns  I want to concatenate first the columns within the dataframe  To do that I have to convert an int column to str   I ve tried to do as follows   mtrx  X 3     mtrx to string columns     X 3      or   mtrx  X 3     mtrx  X 3   astype str    but in both cases it s not working and I m getting an error saying  cannot concatenate  str  and  int  objects   Concatenating two str columns is working perfectly fine

User · Answer

Change data type of DataFrame column   To int   df column name   df column name astype np int64   To str   df column name   df column name astype str

User · Answer

Just for an additional reference   All of the above answers will work in case of a data frame  But if you are using lambda while creating   modify a column this won t work  Because there it is considered as a int attribute instead of pandas series  You have to use str  target attribute   to make it as a string  Please refer the below example   def add zero in prefix df       if df  Hour   lt 10           return  0    str df  Hour     data  str hr     data apply add zero in prefix  axis 1

User · Answer

Use the following code   df column name   df column name astype  str

User · Answer

Warning  Both solutions given   astype   and apply     do not preserve NULL values in either the nan or the None form   import pandas as pd import numpy as np  df   pd DataFrame  None  string  np nan 42   index  0 1 2 3   columns   A     df1   df  A   astype str  df2    df  A   apply str   print df isnull   print df1 isnull   print df2 isnull     I believe this is fixed by the implementation of to string

User · Answer

In  16   df   DataFrame np arange 10  reshape 5 2  columns list  AB     In  17   df Out 17       A  B 0  0  1 1  2  3 2  4  5 3  6  7 4  8  9  In  18   df dtypes Out 18    A    int64 B    int64 dtype  object     Convert a series  In  19   df  A   apply str  Out 19    0    0 1    2 2    4 3    6 4    8 Name  A  dtype  object  In  20   df  A   apply str  0  Out 20    0    Don t forget to assign the result back   df  A     df  A   apply str      Convert the whole frame  In  21   df applymap str  Out 21       A  B 0  0  1 1  2  3 2  4  5 3  6  7 4  8  9  In  22   df applymap str  iloc 0 0  Out 22    0      df   df applymap str

[python] Converting a column within pandas dataframe from int to string

Examples related to python

Examples related to string

Examples related to pandas

Examples related to dataframe

Examples related to int