What happends here?- function

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December 11th, 2012, 08:38 AM

klskl

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What happends here?- function

Hello, I just have a quick question regarding a very simple function, what happends?

Code:

def function():     
z=0     
for i in range(0,5):
         for j in range(1,4):
             z+=j
     print(z) 
function()

December 11th, 2012, 08:50 AM

rrashkin

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Quote:

Originally Posted by klskl

Hello, I just have a quick question regarding a very simple function, what happends?

Code:

def function():     
z=0     
for i in range(0,5):
         for j in range(1,4):
             z+=j
     print(z) 
function()

Well, the way you posted it, nothing would happen because the indentation is screwed up. What it appears to be doing is adding 1+2+3 5 times, that is at the end, z=30.

December 11th, 2012, 09:13 AM

b49P23TIvg

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fix post

You get an IndentationError . Please read the information at my signature to post code.
(use code tags instead of[indent].)

Rashkin was already here!

You can help yourself with print statements:

Code:

def function():     
    z=0     
    for i in range(0,5):
        print('i has value %d'%i)
        for j in range(1,4):
            print('\tj has value %d'%j)
            z+=j
            print('\tz gruesome, %d'%z)
    print(z) 

function()

__________________
[code]Code tags[/code] are essential for python code!

December 11th, 2012, 10:42 AM

klskl

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Quote:

Originally Posted by rrashkin

Well, the way you posted it, nothing would happen because the indentation is screwed up. What it appears to be doing is adding 1+2+3 5 times, that is at the end, z=30.

yes, but why does it do that? How can you see that, if you care to explain I would be grateful

December 11th, 2012, 10:48 AM

rrashkin

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First you set z=0.
The inner-most loop, for j in range(1,4):, makes j=1,2,3 in succession. At each iteration j is added to z and the sum is the new z, z+=j.
You do that 5 times: for i in range(0,5):, where i= 0,1,2,3,4 but is just a loop counter. That is, i is not used in the calculation.

December 11th, 2012, 02:53 PM

klskl

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Join Date: Sep 2012

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Quote:

Originally Posted by rrashkin

Thanks!

What happends here?- function

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