how to replace values of an individual row and specific columns in pandas data frame-CodePudding

I have a data frame with 902 columns. I want to replace all the values of row 0 from columns 214 to 902 by the values stored in a list. For instance:

I have a list like this:

list_a=['item0','item1','item2', 'item3'....'item 688']

I have a data frame like this:

 item0 item1 item2 item3 ...item688
0  x.    y.    z.    w.       i
1  x.    y.    z.    w.       i
2  x.    y.    z.    w.       i
3  x.    y.    z.    w.       i
4  x.    y.    z.    w.       i

my desired output is:

  item0 item1 item2 item3 ...item688
0 item0 item1 item2 item3 ...item688
1  x.     y.    z.    w.       i
2  x.     y.    z.    w.       i
3  x.     y.    z.    w.       i
4  x.     y.    z.    w.       i

Note: The items stored in the list are also the names of the data frame columns from 214 to 902

I tried, but that does not work:

df.iloc[0,214:902] = list_a

How can I achieve this goal? Any help I appreciate!!

CodePudding user response：

ok that is very strange than your solution works with this simple test:

import pandas as pd

df = pd.DataFrame({
    'colA':[True, False, False], 
    'colB': [1, 2, 3],
    'colc':[True, False, False], 
    'colD': [1, 2, 3]
})

df.iloc[0, 1:3] = ['test 1', 'test 2']

The resulting data frame changed from:

    colA    colB    colc    colD
0   True    1   True    1
1   False   2   False   2
2   False   3   False   3

to:

    colA    colB    colc    colD
0   True    test 1  test 2  1
1   False   2   False   2
2   False   3   False   3

That would solve your problem if i am not mistaken right? Can you check or verify your results some how again?

A possible problem might arise with your iloc command because if you want to change column 902 as well, you would have to say df.iloc[0, 212:903]. You could check this with len(df.iloc[0, 1:3]) and len(list_a) to verify that they have the same length.

CodePudding user response：

My solution works:

df.iloc[0,214:902]= list_a