Linked Questions
130 questions linked to/from Why does python use 'else' after for and while loops?
19
votes
8
answers
14k
views
Pythonic ways to use 'else' in a for loop [duplicate]
I have hardly ever noticed a python program that uses else in a for loop.
I recently used it to perform an action based on the loop variable condition while exiting; as it is in the scope.
What is ...
- 87.8k
15
votes
2
answers
4k
views
Why is the purpose of the "else" clause following a "for" or "while" loop? [duplicate]
I am a Python beginner. I find that the else in for-else and while-else is completely unnecessary. Because for and while will finally run to else, and we can use the usual lines instead.
For example:
...
- 353
7
votes
3
answers
5k
views
What is the use of "else" after "for" loop in Python? [duplicate]
It seems both of the below codes are printing the same, then what is the need of "else" block after "for" loop in python.
Code 1:
for i in range(10):
print i
else:
print "after for loop"
...
- 1,308
3
votes
1
answer
5k
views
What is the method for 'If loop does NOT break, run code'? [duplicate]
I am trying to write a for-loop to go through values, and if by the end of the loop it did not break, I want it to run some code. For example:
for i in range(10):
if someCondition:
break
#...
4
votes
4
answers
644
views
What is the benefit(s) of having 'else clause' for the while loop in python? [duplicate]
Any code after while loop will execute when the condition in the while loop becomes False. It is the same for the code in the 'else clause' section of while loop in python. So What's the advantage of ...
- 8,555
3
votes
1
answer
1k
views
Else block without if block in python [duplicate]
I found the Python Code snippet online to print the range of the prime number but the last else block is making no sense to me as it doesn't has corresponding if block
Note
The Indentation of else ...
- 153
2
votes
2
answers
387
views
Python for-else relationship [duplicate]
I can run the below python script without errors.
for n in range(3):
print n
else:
print "done"
But I am puzzled about the else without a matching if.
It does not make sense.
Can some one ...
- 23
2
votes
3
answers
2k
views
How to fix a problem with input() in python? [duplicate]
I'm creating my first program on python. The objective is to get an output of trip cost. In the below code I want python to throw an error and ask user to retry if the input is not a part of the ...
- 158
2
votes
1
answer
3k
views
Necessity of break in nested if statement in a for loop [duplicate]
Why is the break needed in the following code to skip processing of the else statement?
Why doesn't the if evaluation exit the program by itself, without continuing to process the else statement as ...
0
votes
3
answers
1k
views
Order of execution in nested loops in python [duplicate]
I cant understand the difference between those two code blocks, first the correct one is:
number_list=[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13]
prime_list=[]
for i in number_list:
for j in ...
- 11
3
votes
3
answers
172
views
Why does this `else` block work yet it is not on the same level as the `if` case? [duplicate]
This code runs pretty well and generates the wanted list of prime numbers. But the else block that prints our prime numbers is out of block, but it works anyway, can someone explain it to me?
for num ...
- 5,183
1
vote
1
answer
687
views
Alignment of else: under if: in python [duplicate]
I would like to understand why the following python code to find all prime numbers less than n works:
def prime(n):
for q in range(2,n):
for i in range(2,q):
if q%i==0:
...
- 285
-2
votes
1
answer
1k
views
How does putting an if statement inside a loop and an else statement outside the loop work together (in python) [duplicate]
L=eval(input("Enter a list of elements(number): "))
n=len(L)
print("The original list: ")
print(L)
x=int(input("Enter an element to be searched in the list: "))
for i in ...
- 1
0
votes
1
answer
971
views
If-else indentation [duplicate]
I am playing with python3.5 right now. I was working on a simple code, to find the prime numbers less than a given integer. I solved the code more by mistake and I don't know why. This is the code:
n=...
- 35
2
votes
2
answers
214
views
Why it skips else block [duplicate]
We know Python loops have extra features that are not available in most other programming languages. You can put an else block immediately after a loop's repeated interior block.
for i in range(3):
...
- 3,137