如何使用 Pandas 从多列中确定最大值

Question

The code below is example of how I have been attempting to find out what the highest value from multiple columns is, and then putting the highest value into a newly created column, using pandas.

def Alphabet (row):
    AlpFields = ["A", "B", "C", "D", "E", "F"]
    Alp = len(AlpFields)
    AlpCheck = row[:Alp]
    MaxValue = max(AlpCheck)
    if MaxValue == 0:
        return MaxValue, ""
    return MaxValue , AlpFields[AlpCheck.index(MaxValue)]
df.apply(lambda row: Alphabet(row), axis =1)
df['HighestAlphabetScore'] = df.apply(lambda row: Alphabet(row), axis =1)

In this case I am trying to find what the highest value across columns: A, B, C, D, E and F is and then placing this value in the newly created column "Highest Alphabet Score".

However when I run the code the following error comes up:

TypeError: ("'Index' object is not callable", u'occurred at index 0')

I have tried a variety of different things to try and fix the issue, but so far nothing has worked. Any help on what I am possibly doing wrong/any suggestions on how to get around this error would be really appreciated.

Answer 1

For your dataframe df you can call the max function for the column axis and assign the result to a new column.

Say that you need the maximum among only specific columns, then the code would be

df['HighestAlphabetScore'] = df[["A", "B", "C", "D", "E", "F"]].max(axis=1)