[Tutor] dictionary values in strings

[Max Noel]

On May 19, 2005, at 20:49, William O'Higgins wrote:

> I am trying to discover the syntax for call on a dictionary of  
> lists by
> key and index.
>
> The data structure looks like this:
>
> dol = {'key1':['li1','li2','li3'],'key2':['li1','li2','li3'],\
> 'key3':['li1'li2,'li3','']}
>
> The keys are passed to a function as arguments, and I want the  
> value of
> the specified list index.  This is what I *thought* it would look  
> like:
>
> dol.key(argument)[0] # would return li1 when argument equals key1
>
> But that's wrong.  The error I get is this:
> AttributeError: 'dict' object has no attribute 'key'
>
> I don't know how to interpret that error (well, I know I screwed  
> up, but
> ... :-)  Thanks.

     As the error message implies, dictionaries don't have a key  
attribute. They do, however, have a keys() method:

 >>> a = {'foo': 1, 'bar': 2}
 >>> a.keys()
['foo', 'bar']

     And they also have the has_key() method, which can be used to  
test for the presence of a key in a dict:

 >>> a.has_key('foo')
True
 >>> a.has_key('baz')
False


     What you are looking for can be achieved like this:

 >>> dol = {'key1':['li1','li2','li3'],'key2':['li1','li2','li3'],\
... 'key3':['li1', 'li2','li3','']}
 >>> dol['key1'][0]
'li1'



Hope that helps,
-- Max
maxnoel_fr at yahoo dot fr -- ICQ #85274019
"Look at you hacker... A pathetic creature of meat and bone, panting  
and sweating as you run through my corridors... How can you challenge  
a perfect, immortal machine?"