There is a interface 'Counted' that a lot of Clojure data structures
implement to indicate that they provide O(1) for (count).
Thanks,
Stu
On Fri, Mar 13, 2009 at 4:59 AM, Christophe Grand wrote:
>
> Christian Vest Hansen a écrit :
> > I think that count is O(n) for lists, no?
> >
>
> Count is O
Christian Vest Hansen a écrit :
> I think that count is O(n) for lists, no?
>
Count is O(1) for lists but O(n) for a chain of conses.
Clojure
user=> (let [l (apply list (range 10))] (time (dotimes [_ 100]
(count l
"Elapsed time: 169.710116 msecs"
nil
user=> (let [l (apply list (r
On Fri, Mar 13, 2009 at 7:49 AM, Chouser wrote:
>
> On Fri, Mar 13, 2009 at 2:18 AM, Sergio wrote:
>>
>> There are a couple of obvious ones, but also some others that I
>> haven't seen documented (like, map is much faster on lists than on
>> vectors since rest is O(1) for lists).
>
> You're righ
list doesn't do what you think it does. You've just created a list of
one element.
On Fri, Mar 13, 2009 at 12:10 AM, Sergio wrote:
> (def ls (list (range 100)))
--~--~-~--~~~---~--~~
You received this message because you are subscribed to the Google Groups
Sorry =( I am horribly mistaken
I should have taken my time before posting..
But still, I really thought cons on vectors was O(n) base on
PersistentVector.java, line 148 (The version I'm reading is not the
current SVN head, so I don't know if it is that line for you)
Here is the snippet:
On Fri, Mar 13, 2009 at 2:18 AM, Sergio wrote:
>
> There are a couple of obvious ones, but also some others that I
> haven't seen documented (like, map is much faster on lists than on
> vectors since rest is O(1) for lists).
You're right that 'rest' is O(1) for lists, but it's O(1) for vectors a
