Re: Removing the 5th, 10th, 15th ... element of a list

2015-02-17 Thread Udayakumar Rayala
Ah ok. Got it. On Wed, Feb 18, 2015 at 9:13 AM, Fluid Dynamics wrote: > On Tuesday, February 17, 2015 at 10:24:29 PM UTC-5, Udayakumar Rayala > wrote: >> >> Then probably (apply concat) is better than (mapcat identity) isnt it? >> >> What is (cons ::sentinel)? Why do you need it here? >> > > It'

Re: Removing the 5th, 10th, 15th ... element of a list

2015-02-17 Thread Fluid Dynamics
On Tuesday, February 17, 2015 at 10:24:29 PM UTC-5, Udayakumar Rayala wrote: > > Then probably (apply concat) is better than (mapcat identity) isnt it? > > What is (cons ::sentinel)? Why do you need it here? > It'll drop the wrong elements otherwise: => (->> (range 1 22) (partition 5 5 nil)

Re: Removing the 5th, 10th, 15th ... element of a list

2015-02-17 Thread Udayakumar Rayala
Then probably (apply concat) is better than (mapcat identity) isnt it? What is (cons ::sentinel)? Why do you need it here? On Wed, Feb 18, 2015 at 5:58 AM, Fluid Dynamics wrote: > On Tuesday, February 17, 2015 at 6:47:59 PM UTC-5, Ben wrote: >> >> why not (mapcat next)? >> > > Yeah, that should

Re: Removing the 5th, 10th, 15th ... element of a list

2015-02-17 Thread Fluid Dynamics
On Tuesday, February 17, 2015 at 6:47:59 PM UTC-5, Ben wrote: > > why not (mapcat next)? > Yeah, that should work too, though conceptually trimming each part and then reflattening the partition are two separate steps of the computation. :) > The correct answer, obviously, is > > (->> s > (co

Re: Removing the 5th, 10th, 15th ... element of a list

2015-02-17 Thread Ben Wolfson
why not (mapcat next)? On Tue, Feb 17, 2015 at 3:45 PM, Fluid Dynamics wrote: > On Tuesday, February 17, 2015 at 2:21:20 PM UTC-5, Cecil Westerhof wrote: >> >> What is the best way to remove all elements which position (counting from >> 1) is a multiply of five out of a list? >> >> So the list:

Re: Removing the 5th, 10th, 15th ... element of a list

2015-02-17 Thread Fluid Dynamics
On Tuesday, February 17, 2015 at 2:21:20 PM UTC-5, Cecil Westerhof wrote: > > What is the best way to remove all elements which position (counting from > 1) is a multiply of five out of a list? > > So the list: > (1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21) > ​becomes: > (1 2 3

Re: Removing the 5th, 10th, 15th ... element of a list

2015-02-17 Thread Colin Jones
Sounds almost like a mirror image of `clojure.core/take-nth`, so something like this is kind of fun: (defn drop-nth [n coll] (lazy-seq (when-let [s (seq coll)] (concat (take (dec n) s) (drop-nth n (drop n s)) On Tuesday, February 17, 2015 at 1:21:20 PM UTC-6, Cecil Westerhof

Re: Removing the 5th, 10th, 15th ... element of a list

2015-02-17 Thread Colin Yates
+1 And don't forget Eastwood as well :). On a more serious note, I found http://blog.mattgauger.com/blog/2014/09/15/clojure-code-quality-tools/ has some other great tips related to this. On 17 Feb 2015 20:51, "Timothy Baldridge" wrote: > Clearly the answer is a program that runs every snippet p

Re: Removing the 5th, 10th, 15th ... element of a list

2015-02-17 Thread Timothy Baldridge
Clearly the answer is a program that runs every snippet posted to this mailing list through kibit (https://github.com/jonase/kibit). On Tue, Feb 17, 2015 at 1:49 PM, Colin Yates wrote: > Style police would point out zero? and when-not :). > On 17 Feb 2015 20:40, "Cecil Westerhof" wrote: > >> 20

Re: Removing the 5th, 10th, 15th ... element of a list

2015-02-17 Thread Colin Yates
Style police would point out zero? and when-not :). On 17 Feb 2015 20:40, "Cecil Westerhof" wrote: > 2015-02-17 20:26 GMT+01:00 Timothy Baldridge : > >> Tweak as needed: >> >> (keep-indexed >> (fn [i v] >> (if (= 0 (mod i 5)) >> nil >>

Re: Removing the 5th, 10th, 15th ... element of a list

2015-02-17 Thread Cecil Westerhof
2015-02-17 20:26 GMT+01:00 Timothy Baldridge : > Tweak as needed: > > (keep-indexed > (fn [i v] > (if (= 0 (mod i 5)) > nil > v)) > (range 30)) > ​I made the following: ​ ​(defn indexed-sieve [index this-list]

Re: Removing the 5th, 10th, 15th ... element of a list

2015-02-17 Thread Timothy Baldridge
Tweak as needed: (keep-indexed (fn [i v] (if (= 0 (mod i 5)) nil v)) (range 30)) On Tue, Feb 17, 2015 at 12:21 PM, Cecil Westerhof wrote: > What is the best way to remove all elements which position (counting from >

Re: Removing the 5th, 10th, 15th ... element of a list

2015-02-17 Thread Timothy Baldridge
True, that works, but he wants to remove based on element position, not element value. Timothy On Tue, Feb 17, 2015 at 12:28 PM, Ivan L wrote: > this works > > => (filter #(not= (mod % 5) 0) (range 22)) > (1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 21) > > > On Tuesday, February 17, 2015 at 2:21:2

Re: Removing the 5th, 10th, 15th ... element of a list

2015-02-17 Thread Ivan L
this works => (filter #(not= (mod % 5) 0) (range 22)) (1 2 3 4 6 7 8 9 11 12 13 14 16 17 18 19 21) On Tuesday, February 17, 2015 at 2:21:20 PM UTC-5, Cecil Westerhof wrote: > > What is the best way to remove all elements which position (counting from > 1) is a multiply of five out of a list? >