How to rearrange Pandas column sequence?

Question

>>> df =DataFrame({'a':[1,2,3,4],'b':[2,4,6,8]}) >>> df['x']=df.a + df.b >>> df['y']=df.a - df.b >>> df    a  b   x  y 0  1  2   3 -1 1  2  4   6 -2 2  3  6   9 -3 3  4  8  12 -4 

Now I want to rearrange the column sequence, which makes 'x','y' column to be the first & second columns by :

>>> df = df[['x','y','a','b']] >>> df     x  y  a  b 0   3 -1  1  2 1   6 -2  2  4 2   9 -3  3  6 3  12 -4  4  8 

But if I have a long coulmns 'a','b','c','d'....., and I don't want to explictly list the columns. How can I do that ?

Or Does Pandas provide a function like set_column_sequence(dataframe,col_name, seq) so that I can do : set_column_sequence(df,'x',0) and set_column_sequence(df,'y',1) ?

Answer 1

You could also do something like this:

df = df[['x', 'y', 'a', 'b']] 

You can get the list of columns with:

cols = list(df.columns.values) 

The output will produce something like this:

['a', 'b', 'x', 'y'] 

...which is then easy to rearrange manually before dropping it into the first function