#clojure – 2009-07-19

2009-07-19

00:33	hamza	I have an array of integers i would like to find the biggest integer in the array using max but it does not work. is there a way to do it or do i have to roll my own function to iterate and find it?
00:35	durka42	hamza: what have you tried?
00:36	hamza	i was using (max array) but just found the answer (reduce max array) worked thx.
00:36	hamza	should have RTFM
00:40	hiredman	(apply max array)
00:40	hiredman	I wonder if that works
00:41	hiredman	,(apply max (into-array [1 2 3 4]))
00:41	clojurebot	4
00:49	hamza	is it possible to do this to a 2d array?
00:51	hiredman	a. there is no such thing, java arrays are 1d b. yes
00:53	hiredman	,(apply max (reduce #(apply max 5) (into-array (map into-array [[1 2] [3 4] [5 6]])))))
00:53	clojurebot	java.lang.IllegalArgumentException: Wrong number of args passed to: sandbox$eval--2791$fn
00:53	hiredman	,(apply max (reduce #(apply max %) (into-array (map into-array [[1 2] [3 4] [5 6]])))))
00:53	clojurebot	java.lang.IllegalArgumentException: Wrong number of args passed to: sandbox$eval--2798$fn
00:53	hamza	i created an array in repl like (def atest (make-array Integer 5 5)) now if do (reduce max atest) i get class cast exception
00:53	hiredman	bah
00:54	hiredman	,(apply max (into-array (map into-array [[1 2] [3 4] [5 6]])))
00:54	clojurebot	java.lang.ClassCastException: [Ljava.lang.Integer; cannot be cast to java.lang.Number
00:54	hiredman	,(map #(apply max %) (into-array (map into-array [[1 2] [3 4] [5 6]])))
00:54	clojurebot	(2 4 6)
00:54	hiredman	,(apply max (map #(apply max %) (into-array (map into-array [[1 2] [3 4] [5 6]]))))
00:54	clojurebot	6
00:56	hamza	thx alot ill try using this
01:37	fsm	Hi, I have a question about efficiency - I am writing 3d code, which makes heavy use of vectors e.g. [x y z]
01:37	fsm	right now I am using arrays to represent them and 'nth' to access the values
01:38	fsm	is there a more efficient way of reading doubles from a small, fixed-size array like this?
01:42	Jomyoot	There should be emacs built on Clojure
01:44	Jomyoot	IS there IDE with syntax completion yet?
02:02	durka42	does slime do tab completion?
02:02	durka42	vimclojure does some
02:03	replaca	durka42: I've heard that you can get slime to do tab completion, but I haven't succeeded at it myself
02:03	replaca	I think technomancy knows how
03:19	Jomyoot	how to just grab unique entry from a seq?
03:20	duncanm	(first my-seq) ?
03:20	Jomyoot	hmm?
03:20	Jomyoot	that would just get the first one?
03:20	duncanm	the first one is not unique?
03:20	Jomyoot	unique entries
03:21	duncanm	turn it into a set?
03:21	duncanm	,(set '(1 1 1 2 3 4 5 5))
03:21	clojurebot	#{1 2 3 4 5}
03:21	Jomyoot	then it becomes a hash
03:21	Jomyoot	Then how would I make it back into a seq again?
03:21	duncanm	err
03:21	Jomyoot	seq() ?
03:22	duncanm	,(seq (set '(1 1 1 2 3 4 5 5)))
03:22	clojurebot	(1 2 3 4 5)
03:22	Jomyoot	cool
03:22	kotarak	Jomyoot: all the seq functions take also maps, vectors, sets....
03:23	kotarak	,(map inc (set [1 1 1 2 3 4 5 5]))
03:23	clojurebot	(2 3 4 5 6)
03:24	duncanm	la la la
03:24	erohtar	jomyoot: distinct
03:25	erohtar	,(distinct [1 1 2 2 3 3 4 5])
03:25	clojurebot	(1 2 3 4 5)
03:25	duncanm	oh cool
03:25	duncanm	erohtar: good job!
03:25	duncanm	that's neat
03:48	mariorz	how can i tell how much of the heap a collection is taking?
05:21	Jomyoot	what is elegant way to do infinite loop?
05:26	kotarak	(while true ...)
05:26	kotarak	There is no break, though.
05:27	kotarak	If you want to leave the loop at some time do: (def running (atom true)) (while @running .... (when condition (reset! running false)))
05:46	berk	Hi, I am reading Okasaki's book, implementing examples as I go along. I want to create a seq interface (at least conj, first, rest) for the datastructures, in clojure (ie. not ISeq and java). What is the correct way of doing that?
05:51	kotarak	berk: use proxy: (defn seq-from-your-coll [coll] (proxy [clojure.lang.ASeq] (first [] ...) (more [] ...)))
05:55	berk	thanks kotorak, I didn't know about proxy.
05:55	kotarak	berk: it's useful to implement eg interfaces.
05:55	kotarak	some kind of anonymous class.
05:55	kotarak	If it's more involved you can also use gen-class.
05:56	Jomyoot	Lisp is cool
05:56	Jomyoot	I wish I could use Lisp for everything
06:00	cp2	use lisp for your toaster
09:58	rhickey	chunks now in master
09:58	rhickey	but not the mutable vector stuff
11:49	Jomyoot	I want a Classifier in Clojure
11:49	Jomyoot	Naive Bayes or SVM
12:11	Chouser	the commit history in git confuses me
12:13	Chouser	the only thing that appears to be new today is an empty commit
12:16	Jomyoot	Is there Naive Bayes in Clojure already?
12:23	Chousuke	Chouser: it's a merge commit :)
12:23	Chousuke	Chouser: the actual commits are ordered by creation date, so whatever was added is further down in the log.
12:24	Chousuke	Chouser: it helps to use gitk or something to look at it, I guess.
12:25	Chousuke	The merge commit message could have been a bit more informative though :P
12:26	Chousuke	But git autocommits merges by default
12:33	rhickey	Chouser: yeah, I don't get the the forks view either, but the commit was a merge of chunks prior to mutable vector work, so now chunks work is in master
12:46	Jomyoot	Philosophically, is Clojure tied to JVM?
12:46	Jomyoot	Will Clojure eventually support other platform?
12:46	Jomyoot	even native platform?
12:47	Chousuke	hmmh
12:47	Chousuke	to port clojure to "native" code you would have to implement an entire runtime providing GC etc. for it. :/
12:47	Jomyoot	Does RIch Hickey view JVM as "THE" platform?
12:48	Jomyoot	or just one of the platforms
12:49	Chousuke	That I don't know. There are already attempts for "ports" to other platforms, but because clojure tries to tightly integrate with the host system, I don't think the ports can ever be 100% compatible with implementations on other hosts.
12:50	Chousuke	of course, if your clojure code never uses host interop and only core.clj, then it could be compatible with any clojure implementation, providing they supply a working version of core.clj
12:59	pronik	hi, is clojure-contrib supposed to be compilible with clojure 1.0 release (as opposed to current HEAD)?
13:01	Chousuke	the master branch is not.
13:01	Chousuke	there's a clojure-1.0-compatible branch
13:07	pronik	ok, thanks
13:12	Chousuke	No, no, no. Nothing of the sort. Idea is different and it's somewhat simpler:
13:12	Chousuke	1. Behavior is undefined so program can do anything it wants. It can destroy the world for god's sake!
13:12	Chousuke	2. Program which can destroy the world is pretty useless so obviously people will not write such program.
13:12	Chousuke	oops.
13:12	Chousuke	drag&drop fail :P
13:43	Drakeson	how would you recursively search (e.g., with a pred) on zips? (e.g. zip/xml-zip)
17:26	maacl	Is anybody else having problems with clojure-update from clojure-mode?
17:31	maacl	ah - the repo has been changed
17:54	maacl	Using emacs/slime what would cause (ns test (:use [clojure-contrib server-socket])) not to work while (use 'clojure.contrib.server-socket) works?
18:07	Chousuke	maacl: because you need a list, like (clojure-contrib server-socket), not a vector
18:08	maacl	Chousuke: oh, has this been changed at some point?
18:08	Chousuke	It has always been like that as far as I know.
18:08	Chousuke	it's a prefix list. a vector is used for libspecs
18:09	Chousuke	eg. (:use (prefix lib [lib2 :as somealias] lib3))
18:13	maacl	that is odd - the code for the clojure peepcode screencast - the mire mud uses a vector
18:23	maacl	Chousuke: changing it to a lost doesn't fix it - this is really weird
18:26	Chousuke	wait, hm
18:26	Chousuke	it's clojure.contrib, not clojure-contrib .P
18:27	Chousuke	:use etc. need to be redone anyway. :/
18:27	Chousuke	there was some discussion here earlier but I don't think anyone did anything. hmm
18:28	Chousuke	oh well, I'll get some sleep for now.