How to convert pandas dataframe max index values into string?-CodePudding

I am working with a pandas dataframe consisting of "recipients" on the y axis and "donors" on the x.

            Donor1  Donor2  Donor3  Donor4  Donor5  Donor6
Recipient1       0       4       1       4       7       6
Recipient2       6       0       9       8       5       8
Recipient3       5       3       5       0       9       3
Recipient4       9       2       1       8       0       5
Recipient5       4       5       5       9       4       2
Recipient6       5       4       2       8       5       6

The maxValueIndex code

maxValueIndex = df_test_bid.idxmax(axis = 1)
print(str(maxValueIndex))

produces: (index of max value in that row)

Recipient1    Donor5
Recipient2    Donor3
Recipient3    Donor5
Recipient4    Donor1
Recipient5    Donor4
Recipient6    Donor4
dtype: object

How can I convert each recipient/donor pair into a single string? In other words, how can I iterate through each recipient/donor pair?

Trying to iterate with a for loop only gets me the donors.

CodePudding user response：

if you want to convert 2 columns to one:

dataframename.apply(lambda x: str(x["<first_col_name>"])   " "   str(x["<second_col_name>"]), axis = 1)

CodePudding user response：

The issue is that idxmax creates a pd.Series with Recipients as the index. To loop through them as expected, try:

df2 = df.idxmax(axis=1)
for i, x in df2.iteritems():
    print(i   ' '   x)

Output:

Recipient1 Donor5
Recipient2 Donor3
Recipient3 Donor5
Recipient4 Donor1
Recipient5 Donor4
Recipient6 Donor4

To use the more panda's friendly way, convert the output to a dataframe and reset the index:

df2 = df.idxmax(axis=1)
df2 = pd.DataFrame(df2).reset_index()
df2 = df2.apply(lambda x: x['index']   ' '   x[0], axis=1)
print(df2)

Output:

0    Recipient1 Donor5
1    Recipient2 Donor3
2    Recipient3 Donor5
3    Recipient4 Donor1
4    Recipient5 Donor4
5    Recipient6 Donor4