Iteration WAS working in my script, now I cant get python to iterate - what happened?
Did my python ide break or something?
import sys
i = 0
sample = ("this", "is", "Annoying!")
for line in sample:
print i, line
i + 1
Now gives me...
0 this 0 is 0 Annoyin开发者_如何学JAVAg!
I THOUGHT, it would give me:
1 this 2 is 3 Annoying
I had other scripts that I was working on and it they all just broke - they all have the same line number when they print numerous iterations using the for statement - can someone PLEASE tell me what the heck is going on - very frustrated lol... did Python break? Do I need sleep? What is wrong here?
While the other answers are correct, this is how you usually do this in python:
sample = ("this", "is", "Annoying!")
for i, line in enumerate(sample):
print i, line
The enumerate
function does exactly what you want: Iterating through your tuple, while at the same time giving you (line) numbers.
You are calculating i+1
but are not storing the result of that anywhere. Specifically you are not updating i
to contain the new value. Use i = i + 1
or i += 1
instead.
This works just fine for me:
>>> import sys
>>> i = 0
>>> sample = ("abc", "def", "ghi")
>>> for line in sample:
... i = i + 1
... print i, line
...
1 abc
2 def
3 ghi
Are you sure you're incrementing and storing the value i
? (Your sample omits this, but in another answer you say you did put i = i + 1
.) Remember, Python is whitespace-sensitive, so if you did something like this, the result won't be what you expect:
>>> for line in sample:
... print i, line
... i = i + 1 # <-- This is not part of the loop!
I suspect you have an indentation problem, that perhaps the i = i + 1 statement is somehow not part of the for-loop.
But Instead of doing your own counter incrementing, better practice is to use enumerate:
for i,line in enumerate(sample):
print i,line
The problem is you're doing "i + 1", not "i=i+1"
You're not incrementing the variable i
in your code, you'd need to do something like:
for line in sample:
i = i + 1
print i, line
The result that you expect would be obtained by using enumerate:
sample = ("this", "is", "Annoying!")
for index, line in enumerate(sample):
print index, line
I don't see how the code that you posted ever would have worked in any version of Python.
Just step through debugger to see the execution.
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