Re: [Factor-talk] List Comprehension in Factor

2013-05-22 Thread John Benediktsson
> > How come "rest" doesn't just use a virtual sequence to offset the > original index by 1. > You're thinking of "rest-slice", which is a virtual version of "rest". -- Try New Relic Now & We'll Send You this Cool Shirt Ne

Re: [Factor-talk] List Comprehension in Factor

2013-05-22 Thread mr w
> I'm glad the final version is so elegant! > > Best, > John. "Chuck Moore declared that the software problem was solved and that the remaining problem was hardware." -- http://www.ultratechnology.com/ With the software problem solved, maybe the remaining problems are hardware and pure math. -

Re: [Factor-talk] List Comprehension in Factor

2013-05-22 Thread mr w
On Wed, May 22, 2013 at 8:58 AM, John Benediktsson wrote: > Using ranges, "iota rest" is just "[1,b)" (and more memory efficient because > rest causes the virtual sequence to become concrete). How come "rest" doesn't just use a virtual sequence to offset the original index by 1. ---

Re: [Factor-talk] List Comprehension in Factor

2013-05-22 Thread John Benediktsson
Using ranges, "iota rest" is just "[1,b)" (and more memory efficient because rest causes the virtual sequence to become concrete). The filter-combinations word is more efficient than all-combinations [ ... ] filter because it can ignore or skip the ones that are not triples as it builds the res

Re: [Factor-talk] List Comprehension in Factor

2013-05-22 Thread mr w
wrote: >> Oo, or even >> >> >> : triples ( n -- seq ) >> iota rest 3 [ first3 triple? ] filter-combinations ; Out of all the examples given in several languages, this is by far the most concise version. -- Try New Re

Re: [Factor-talk] List Comprehension in Factor

2013-05-22 Thread mr w
On Mon, May 20, 2013 at 10:11 PM, Alex Vondrak wrote: > Oo, or even > > > : triples ( n -- seq ) > iota rest 3 [ first3 triple? ] filter-combinations ; Does filter-combinations filter as it builds the list? Or does it build the list then filter it? ---

Re: [Factor-talk] List Comprehension in Factor

2013-05-20 Thread Alex Vondrak
Oo, or even : triples ( n -- seq ) iota rest 3 [ first3 triple? ] filter-combinations ; On Mon, May 20, 2013 at 7:06 PM, Alex Vondrak wrote: > Or, going by the algorithms in the wiki: > > ``` > USING: arrays kernel locals math math.ranges sequences > sequences.extras ; > > :: triples ( n -

Re: [Factor-talk] List Comprehension in Factor

2013-05-20 Thread Alex Vondrak
Or, going by the algorithms in the wiki: ``` USING: arrays kernel locals math math.ranges sequences sequences.extras ; :: triples ( n -- seq ) n [1,b] [| x | x n [a,b] [| y | y n [a,b] [| z | x sq y sq + z sq = ] [| z | x y z 3array ] fi

Re: [Factor-talk] List Comprehension in Factor

2013-05-20 Thread _ _
! Copyright (C) 2013 Your name. ! See http://factorcode.org/license.txt for BSD license. USING: kernel sequences math math.functions arrays math.combinatorics ; IN: pythagorean-triples : a-b-list ( n -- seq ) iota rest 2 all-combinations ; : a-b-c ( seq1 -- seq2 ) [ first ] [ second ]

Re: [Factor-talk] List Comprehension in Factor

2013-05-20 Thread John Benediktsson
We don't have "list comprehensions", per se - but instead have basic map and filter operations... Instead of [ x for x in range(5) if x % 2 == 0 ] We would have: 5 iota [ 2 mod zero? ] filter Instead of [ x ** 3 for x in foo() ] We would have: foo [ 3 ^ ] map You could use

Re: [Factor-talk] list

2009-09-26 Thread Slava Pestov
On Sat, Sep 26, 2009 at 8:44 PM, Hugh Aguilar wrote: > For example, I want to find a node in the list and split the list into two > lists at that point. With sequences, the function find returns an index into > the sequence. None of the spliting functions take an index however. All of > them are s

Re: [Factor-talk] list

2009-09-26 Thread Chris Double
On Sun, Sep 27, 2009 at 1:44 PM, Hugh Aguilar wrote: > None of the spliting functions take an index however. All of > them are splitting on a particular subsequence. I think you want 'cut' or 'cut*'. This is in the "Subsequences and Slices" part of the help. Chris. -- http://www.bluishcoder.co.

Re: [Factor-talk] list

2009-05-30 Thread Slava Pestov
On Fri, May 29, 2009 at 11:03 PM, Hugh Aguilar wrote: > I'm aware of unit testing, having read about it in a book: "Foundations of > Agile Python Development" (Jeff Younker). I don't have much experience with > it in any language though (I'm learning Python simultaneously with learning > Factor).

Re: [Factor-talk] list

2009-05-27 Thread Kobi Lurie
Hi Hugh, are you aware of unit testing? it's very simple and short to write. In other languages it's sometimes a pain, but here it's very short. you should try it, instead of the test utils at the end :-) Kobi Slava Pestov wrote: > Hugh, > > What you've implemented is like Factor's dlists, > htt

Re: [Factor-talk] list

2009-05-26 Thread Slava Pestov
Hugh, What you've implemented is like Factor's dlists, http://docs.factorcode.org/content/article-dlists.html. They are an implementation of the deque abstract data type, http://docs.factorcode.org/content/article-deques.html Slava On Tue, May 26, 2009 at 11:59 PM, Hugh Aguilar wrote: > Here i

Re: [Factor-talk] list of word callers

2008-12-20 Thread Joe Groff
On Dec 20, 2008, at 11:11 AM, Jose A. Ortega Ruiz wrote: > I'd like to implement a FUEL command displaying the list of callers > of a > given word. Is there an easy way to ask factor for them? The "usage." word will do what you want. \ swap usage. -Joe ---