Loops and things

[rocco.rossi@gmail.com]

I was wondering how and if it's possible to write a loop in python
which updates two or more variables at a time. For instance, something
like this in C:

for (i = 0, j = 10; i < 10 && j < 20; i++, j++) {
printf("i = %d, j = %d\n", i, j);
}

So that I would get:

i = 0, j = 0
i = 1, j = 1
i = 2, j = 2
....
....
....
i = 9, j = 19

Can this be done in Python?

Thanks.

[Neil Cerutti]

Re: Loops and things

On 2007-12-14, rocco.rossi@gma il.com <rocco.rossi@gm ail.comwrote:

I was wondering how and if it's possible to write a loop in python
which updates two or more variables at a time. For instance, something
like this in C:
>
for (i = 0, j = 10; i < 10 && j < 20; i++, j++) {
printf("i = %d, j = %d\n", i, j);
}
>
So that I would get:
>
i = 0, j = 0
i = 1, j = 1
i = 2, j = 2
...
...
...
i = 9, j = 19
>
Can this be done in Python?

Yes, assuming you meant to say:

i = 0, j = 10
i = 0, j = 11
....
i = 9, j = 19

import sys
from itertools import izip

for i, j in izip(xrange(10) , xrange(10, 20)):
sys.stdout.writ e("i = %d, j = %d\n", (i, j))

--
Neil Cerutti
To succeed in the world it is not enough to be stupid, you must also be well-
mannered. --Voltaire

[i.pantusa@gmail.com]

Re: Loops and things

On Dec 14, 5:01 pm, Neil Cerutti <horp...@yahoo. comwrote:

On 2007-12-14, rocco.ro...@gma il.com <rocco.ro...@gm ail.comwrote:
>
>
>

I was wondering how and if it's possible to write a loop in python
which updates two or more variables at a time. For instance, something
like this in C:

>

for (i = 0, j = 10; i < 10 && j < 20; i++, j++) {
printf("i = %d, j = %d\n", i, j);
}

>

So that I would get:

>

i = 0, j = 0
i = 1, j = 1
i = 2, j = 2
...
...
...
i = 9, j = 19

>

Can this be done in Python?

>
Yes, assuming you meant to say:
>
i = 0, j = 10
i = 0, j = 11
...
i = 9, j = 19
>
import sys
from itertools import izip
>
for i, j in izip(xrange(10) , xrange(10, 20)):
sys.stdout.writ e("i = %d, j = %d\n", (i, j))
>
--
Neil Cerutti
To succeed in the world it is not enough to be stupid, you must also be well-
mannered. --Voltaire

Yeah, that's what I meant ... ooops :)

Thanks a lot to everyone for the useful info. In the meantime I had
found out about zip and that way of doing it. But I really appreciated
all the different alternative solutions that were illustrated,
especially the more "functional " ones with map ... very cool, I'm also
a big Lisp fan, and I really dig those.