Max function in python returning wrong results

Question

I am trying to find the Max and Min in a set of numbers from a CSV file. My code keeps returning the wrong number for Max function for some rows. Here is my code:

with open('Cortex_vs_Liver_trial.csv', newline='') as infile:
    reader = csv.reader(infile)

    for row in reader:
        print(row)
        print('The maximun is:', max(row))
        print('The minimum is:', min(row))

An example of my output:

['86.21', '100.00', '96.30']
The maximun is: 96.30
The minimum is: 100.00

I am not sure what I have done wrong. Some advice would be appreciated.

You're comparing strings not numeric data. Use: max (col[3:6], key=float) — Ashwini Chaudhary

mhlester mhlester · Accepted Answer · 2014-02-12T17:39:10

Your list elements are strings. You need to convert them to float to avoid comparing lexicographically (alphabetically, one character at a time, where '100' < '2' because 1 < 2)

numrow = [float(x) for x in row]
print('The maximun is:', max(numrow))
print('The minimum is:', min(numrow))

Unless you actually want strings, in which case don't make the new list, and just pass key=float to your max() function:

max(numrow, key=float)

Max function in python returning wrong results

1 Answers