Why my code is not able to convert each item of list from string to integer?

Question

I am stuck on a problem due to a small portion of my code. I can't find why that portion of code is not working properly.

By debugging each portion of my code, I found which lines are causing unexpected results. I have written that lines below. I have defined the list here so that I do not have to copy my full code.

list1=["-7","-7","-6"]

for test in list1:

    test=int(test)

print( type( list1[0] ) )

I expected type to be int but output is coming as str instead.

You are not storing the converted `test` anywhere. It is lost in the next iteration. — rdas, May 30 '19 at 08:47
Save your converted items to a list, perhaps `li.append(int(test))` — Devesh Kumar Singh, May 30 '19 at 08:48
You did not the list entries You have created a test var which is int — balderman, May 30 '19 at 08:49

score 3 · Answer 1 · answered May 30 '19 at 08:47

3

You need to modify the content of the list:

list1=["-7","-7","-6"]

for i in range(len(list1)):
    list1[i] = int(list1[i])

print(type(list1[0]))

A more pythonic approach would be to use a comprehension to change it all at once:

list1 = [int(x) for x in list1]

answered May 30 '19 at 08:47

Netwave

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Thanks for helping me – Udit Garg Jun 03 '19 at 16:55

score 0 · Answer 2 · answered May 30 '19 at 08:48

0

Try this to convert each item of a list to integer format :

list1=["-7","-7","-6"]
list1 = list(map(int, list1))

list1 becomes [-7, -7, -6].

Now type(list1[0]) would be <class 'int'>

answered May 30 '19 at 08:48

Arkistarvh Kltzuonstev

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score 0 · Answer 3 · answered May 30 '19 at 08:51

0

You forgot about appending the transformed value:

list1 = ["-7","-7","-6"]
list2 = [] # store integers
for test in list1:
    test = int(test)
    list2.append(test) # store transformed values

print(type(list2[0]))

answered May 30 '19 at 08:51

balkon16

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Thanks for helping – Udit Garg Jun 03 '19 at 16:56
You can upvote my answer if it answers your question :) – balkon16 Jun 04 '19 at 05:31
1

I have upvoted your answer but it will not come public as I have reputation less than 15. – Udit Garg Jun 10 '19 at 09:31

Why my code is not able to convert each item of list from string to integer?

3 Answers3