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Re: lisp can sum a list of numbers with 2 parens and a +, can forth useloop to make something similar?

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On Mon, 09 Feb 2015 08:00:02 -0500, Doug Hoffman wrote:

> On 2/9/15 3:55 AM, WJ wrote:
> 
>> Calculate the average of the numbers in a list, traversing it only once
>> and making no assignments to a variable:
>>
>> Gauche Scheme:
>>
>> (define (average numbers)
>>    (apply /
>>      (fold (lambda (x accum) (map + (list x 1) accum))
>>            '(0 0)
>>            numbers)))
>>
>> (define numbers `(,@(iota 9 -9 2) 633 ,@(iota 9 22))) numbers
>>   ===>
>> (-9 -7 -5 -3 -1 1 3 5 7 633 22 23 24 25 26 27 28 29 30)
>>
>> (average numbers)
>>   ===>
>> 858/19
>>
>> (inexact (average numbers))
>>   ===>
>> 45.1578947368421
>>
>>
>> The easy way would be
>>
>> (/. (apply + numbers) (length numbers))
>>   ===>
>> 45.1578947368421
>>
>> but that traverses the list twice: once to add up the numbers and once
>> to determine the length of the list.
> 
> 
> : ave{ 0e 0
>    begin parse-name 2dup s" }" compare
>    while >float drop f+ 1+
>    repeat 2drop s>f f/ f. ;
> 
> ave{ -9 -7 -5 -3 -1 1 3 5 7 633 22 23 24 25 26 27 28 29 30 }
> 45.1578947368421 ok
> 
> \ the easier way would be to use library code: f{ -9 -7 -5 -3 -1 1 3 5 7
> 633 22 23 24 25 26 27 28 29 30 } average: f. 45.1578947368421 ok

Computing is no longer 'about computors' it's about human cognition:
saving effort. Yes, minimal text is part of saving-effort.
But recognise & select [ie. menu] instead of 'coding' is cheaper.
Also color economically adds cognitive power.
Where's the VISUAL forth?

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lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? the_gavino_himself <visphatesjava@gmail.com> - 2015-01-22 19:34 -0800
  Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? foxaudioresearch@gmail.com - 2015-01-22 20:08 -0800
    Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? Mark Wills <markwills1970@gmail.com> - 2015-01-23 02:00 -0800
    Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? Coos Haak <chforth@hccnet.nl> - 2015-01-23 14:07 +0100
      Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? "WJ" <w_a_x_man@yahoo.com> - 2015-01-24 01:43 +0000
      Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? beeflo <beeflobill@gmail.com> - 2015-01-29 08:22 -0800
        Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? "Elizabeth D. Rather" <erather@forth.com> - 2015-01-29 11:35 -1000
          Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-01-30 16:20 +0000
            Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? Bernd Paysan <bernd.paysan@gmx.de> - 2015-01-30 21:48 +0100
    Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? the_gavino_himself <visphatesjava@gmail.com> - 2015-01-23 13:09 -0800
    Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? empty-buffers <empty.buffersYOU-DONT-WANT-THIS@gmail.NEITHER-THIS.com> - 2015-01-29 00:38 +0000
      Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? Coos Haak <chforth@hccnet.nl> - 2015-01-29 02:49 +0100
      Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? "Elizabeth D. Rather" <erather@forth.com> - 2015-01-28 16:34 -1000
  Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? the_gavino_himself <visphatesjava@gmail.com> - 2015-01-29 16:04 -0800
    Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? Paul E Bennett <Paul_E.Bennett@topmail.co.uk> - 2015-01-30 08:46 +0000
  Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? skydda.barnen@gmail.com - 2015-01-30 02:39 -0800
    Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? "Alex McDonald" <blog@rivadpm.com> - 2015-01-30 11:32 +0000
      Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? lehs <skydda.barnen@gmail.com> - 2015-01-30 04:08 -0800
      Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? lehs <skydda.barnen@gmail.com> - 2015-01-30 08:38 -0800
        Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? Coos Haak <chforth@hccnet.nl> - 2015-01-30 22:01 +0100
          Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? lehs <skydda.barnen@gmail.com> - 2015-01-30 22:16 -0800
            Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? Coos Haak <chforth@hccnet.nl> - 2015-02-01 00:23 +0100
              Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? lehs <skydda.barnen@gmail.com> - 2015-02-01 00:35 -0800
                Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? Coos Haak <chforth@hccnet.nl> - 2015-02-01 14:20 +0100
                Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? lehs <skydda.barnen@gmail.com> - 2015-02-01 07:42 -0800
                Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-02-01 17:24 +0000
                Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? lehs <skydda.barnen@gmail.com> - 2015-02-01 09:58 -0800
                Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-02-02 00:46 +0000
                Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? "Elizabeth D. Rather" <erather@forth.com> - 2015-02-01 08:59 -1000
                Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? lehs <skydda.barnen@gmail.com> - 2015-02-01 12:06 -0800
                Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? hughaguilar96@gmail.com - 2015-02-08 18:43 -0800
                Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? Ron Aaron <rambamist@gmail.com> - 2015-02-09 08:36 +0200
    Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-01-30 16:27 +0000
      Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? lehs <skydda.barnen@gmail.com> - 2015-02-01 01:24 -0800
        Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-02-01 16:13 +0000
          Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? lehs <skydda.barnen@gmail.com> - 2015-02-01 10:54 -0800
  Re: lisp can sum a list of numbers with 2 parens and a +, can forth use loop to make something similar? hughaguilar96@gmail.com - 2015-02-08 18:07 -0800
  Re: lisp can sum a list of numbers with 2 parens and a +, can forth useloop to make something similar? "WJ" <w_a_x_man@yahoo.com> - 2015-02-09 08:55 +0000
    Re: lisp can sum a list of numbers with 2 parens and a +, can forth useloop to make something similar? Doug Hoffman <glidedog@gmail.com> - 2015-02-09 08:00 -0500
      Re: lisp can sum a list of numbers with 2 parens and a +, can forth useloop to make something similar? Unknown <dog@gmail.com> - 2015-02-11 09:19 +0000

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