[Tutor] Re: prepend variable name...

[don arnold]

----- Original Message -----
From: "don arnold" <darnold02 at sprynet.com>
To: "kevin parks" <kp8 at mac.com>
Cc: <tutor at python.org>
Sent: Tuesday, January 20, 2004 5:54 AM
Subject: Re: [Tutor] Re: prepend variable name...


> ----- Original Message -----
> From: "kevin parks" <kp8 at mac.com>
> To: "kevin parks" <kp8 at mac.com>
> Cc: <tutor at python.org>
> Sent: Tuesday, January 20, 2004 1:01 AM
> Subject: [Tutor] Re: prepend variable name...
>
>
> > I should add that, i think the answer lies in making a dictionary (with
> > zip?), but what i am not sure of is how to then traverse a dictionary
> > in order...
> >
>
> Yes, a dictionary is your best option (though zip doesn't enter the
picture,
> here). In fact, Danny just answered this same question a couple of days
ago
> with his 'fruitbasket' example. Instead of using a 'regular' variable to
> hold your data, you use the variable name as a dictionary key and store
your
> data there:
>
> myvars = {}
> myvars['exI_2a'] = [11,5,7,2]
> myvars['exI_2b'] = [0,10,5]
> myvars['exI_2c'] = [7,6,9,1]
> myvars['exI_2d'] = [4,7,2,7,11]
>
> for key in myvars:
>     print key
>     print data
>     print

Sloppy cut and paste on my part. The above block should read:

for key in myvars:
    print key
    print myvars[key]
    print

>
> [--output--]
>
> exI_2d
> [4, 7, 2, 7, 11]
>
> exI_2c
> [7, 6, 9, 1]
>
> exI_2b
> [0, 10, 5]
>
> exI_2a
> [11, 5, 7, 2]
>
> You'll notice that the items aren't necessarily in key order. This is
> because a dictionary is an unordered collection. To get around this, you
can
> use the dicionary's keys() method to generate a list of its keys, then
sort
> this list before iterating over it.
>
> myvars = {}
> myvars['exI_2a'] = [11,5,7,2]
> myvars['exI_2b'] = [0,10,5]
> myvars['exI_2c'] = [7,6,9,1]
> myvars['exI_2d'] = [4,7,2,7,11]
>
> keylist = myvars.keys()
> keylist.sort()
> for key in keylist:
>     print key
>     print myvars[key]
>     print
>
> [--output--]
>
> exI_2a
> [11, 5, 7, 2]
>
> exI_2b
> [0, 10, 5]
>
> exI_2c
> [7, 6, 9, 1]
>
> exI_2d
> [4, 7, 2, 7, 11]
>
>
> > gosh... dictionaries... hmm... we didn't have those in C so i find that
> > i forget how versatile they are. Anyway, i haven't really answered my
> > own question yet... but i am i headed in the right direction?
> >
> > -kp--
>
> Most definitely.
>
> HTH,
> Don
>

Sorry about that,
Don