How to find index of an array which has maximum value in dataframe using python?

Question

I have a dataframe which has array of elements, i would like to get the index value of the maximum number in the array using python,

Desired output:

Elements    Max Value Index

[3,4,5]              2

[2,0,1]              0

I tried using:

df['Max Value Index'] = df["Elements"].apply(lambda x:max(x))

It gives me the maximum value, , I just need the index number, i tried many ways but not able to get that, can anybody please help?

Ravindra S · Accepted Answer · 2022-06-23 08:48:52Z

1

Try idxmax(x)

df['Max Value Index'] = df["Elements"].apply(lambda x:idxmax(x))

answered Jun 23, 2022 at 8:48

Ravindra S

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Comments

Nick · Accepted Answer · 2022-06-23 08:49:39Z

1

You could use numpy.argmax:

df['Max Value Index'] = df['Elements'].apply(lambda l:np.argmax(l))

Or in straight python:

df['Max Value Index'] = df["Elements"].apply(lambda l:l.index(max(l)))

Output:

    Elements  Max Value Index
0  [3, 4, 5]                2
1  [2, 0, 1]                0

answered Jun 23, 2022 at 8:49

Nick

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