Can anyone plz explain me about working of FOR LOOP in PYTHON with an example?

Question

I think logical working of for loop in Python is different from the logic of for loop in other languages such as c,c++,java...so I am not able to understand correctly in case of Python.

Answer 1

A for loop is mainly for using a standard variable as you iterate through an iterable, such as a list/dictionary/tuple/etc., and do something with the values contained within, while utilizing that variable.

In the following, a list is created, then the values are iterated through in a for loop using "value" with each iteration as a variable for the new increment within the iterable:

list_a = [0,1,2,3,4,5,6,7,8,9]

for value in list_a:
print(value)

or the for loop as a list comprehension:

[print(value) for value in range(0,9)]

Remember the length of the iterable is the range of the loop, unless there is a conditional if.

Also, the python documentation is very extensive when needing in depth explanations.

Answer 2

You are right, there is a difference between for loops in Python and for example C. In C you define a halting condition and an iteration step, while in Python you iterate over the items of any iterable object.
The Python tutorial and language reference do a great job at explaining what that means without leaving any guesswork:
https://docs.python.org/3/tutorial/controlflow.html#for-statements
https://docs.python.org/3/reference/compound_stmts.html#for

Iterable and iterator have very precise meanings, to be found here:
https://docs.python.org/3/glossary.html

Answer 3

for i in range(10):

i is a variable. since we are for looping thru a range of 10, it represents whatever number the loop is on.

for i in range(10):
run #1 .. i=0
run #2 .. i=1

if we had a list we wanted to iterate thru, i is each item in the list. like this

mylist=["a", "b", "c"]
for i in mylist:
run #1 .. i="a"
run #2 .. i="b"

in my personal opinion, Python for loop is easier than Java

for i in range(10):

vs

for(int i=0; i <10; i++){

}

and

for i in myList:

vs

for(String letter: myList){

}

Answer 4

Learn more about Loop and Control statements

http://net-informations.com/JUMP_LINK__&&__python__&&__JUMP_LINK/flow/loop.htm