Get loop count inside a for-loop

python for-loop

This for loop iterates over all elements in a list:

for item in my_list:
    print item

Is there a way to know within the loop how many times I've been looping so far? For instance, I want to take a list and after I've processed ten elements I want to do something with them.

The alternatives I thought about would be something like:

count=0
for item in my_list:
    print item
    count +=1
    if count % 10 == 0:
        print 'did ten'

Or:

for count in range(0,len(my_list)):
    print my_list[count]
    if count % 10 == 0:
        print 'did ten'

Is there a better way (just like the for item in my_list) to get the number of iterations so far?

You might also be interested in the answers to iterating over a list in chunks: stackoverflow.com/questions/434287/…

possible duplicate of Accessing the index in Python for loops

Mateen Ulhaq

The pythonic way is to use enumerate:

for idx, item in enumerate(my_list):

Super duper , Just one magic line solving all problems

Vikram Garg

Agree with Nick. Here is more elaborated code.

#count=0
for idx, item in enumerate(list):
    print item
    #count +=1
    #if count % 10 == 0:
    if (idx+1) % 10 == 0:
        print 'did ten'

I have commented out the count variable in your code.

You could also use enumerate's optional start parameter to start enumerating with 1 instead of 0, though then I'd use the OP's name count instead of idx.

Hans Ginzel

Using zip function we can get both element and index.

countries = ['Pakistan','India','China','Russia','USA']

for index, element in zip(range(0,countries),countries):

         print('Index : ',index)
         print(' Element : ', element,'\n')

output : Index : 0 Element : Pakistan ...

See also :

Python.org

hephestos

I know rather old question but....came across looking other thing so I give my shot:

[each*2 for each in [1,2,3,4,5] if each % 10 == 0])

Vatsal Dutt

This is something you can also do to check for the list index. When it hits the list index 9, which is the 10th element of the list, it will print "did ten".

for item in list:
    print item
    if list.index(item) == 9:
        print 'did ten'

This won't work for lists with duplicate elements like [0, 1, 2, 0]

This will fail when the list has duplicate elements.

Get loop count inside a for-loop

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