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Re: I am still kinda depressed about learning forth

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Hugh Aguilar wrote:

> Your method of learning is completely wrong. You are expecting to read
> books and manuals to learn, and then with all of this wonderful
> knowledge begin to write "lean mean programs and utilize abstraction."
> That is not how it works at all. You must write a program, and then
> read up on the language to figure out how to improve the program. I
> already gave you a practice problem:
> 
> https://groups.google.com/group/comp.lang.forth/browse_thread/thread/d89e033a1b268772
> 
> I said this:
> 
> On Jul 7, 2:35 pm, Hugh Aguilar <hughaguila...@yahoo.com> wrote:
> > Here is a programming challenge easy enough that even Gavino should
> > succeed at it (although I doubt that John Passaniti or Elizabeth
> > Rather can do it). Write a program in ANS-Forth to read a seq file
> > containing one integer per line. Calculate the following: range of
> > data, average of data, median of data, and how many data are above and
> > below the average.
> > 
> > For extra credit, generate a PostScript file that displays a bar-graph
> > of the distribution of data with the mean and median marked.
> > 
> > Everybody please wait a week or two with your answer, in order to give
> > Gavino time to write his program --- this challenge is mostly for his
> > benefit --- it is okay to give him hints (my own hint is to use the
> > novice package's lists), but let him write his own code before you
> > show him your code.

Since Gavino is interested in learning Lisp and Scheme,
here's a solution in Racket.

;; Lines containing numbers must not have whitespace.
;; Blank lines are ignored.
(define numbers 
  (with-input-from-file "data.txt"  (lambda()
    (sort (filter-map string->number (sequence->list (in-lines))) <))))

;; numbers must be already sorted.
(define (median numbers)
  (define i (floor (/ (sub1 (length numbers)) 2)))
  (if (odd? (length numbers))
    (list-ref numbers i)
    (/ (apply + (take (drop numbers i) 2)) 2)))


(printf "range: ~a .. ~a\n" (first numbers) (last numbers))
(define average (/ (apply + numbers) (length numbers)))
(printf "average: ~a\n" average)
(printf "median: ~a\n" (median numbers))
(printf "below average: ~a\n" (length (filter (curry > average) numbers)))
(printf "above average: ~a\n" (length (filter (curry < average) numbers)))

 ==>

range: 3 .. 22
average: 8
median: 13/2
below average: 5
above average: 2

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I am still kinda depressed about learning forth quiet_lad <gavcomedy@gmail.com> - 2012-07-10 21:17 -0700
  Re: I am still kinda depressed about learning forth quiet_lad <gavcomedy@gmail.com> - 2012-07-10 21:43 -0700
  Re: I am still kinda depressed about learning forth marko <marko@marko.marko> - 2012-07-11 14:55 +1000
    Re: I am still kinda depressed about learning forth quiet_lad <gavcomedy@gmail.com> - 2012-07-10 21:57 -0700
      Re: I am still kinda depressed about learning forth marko <marko@marko.marko> - 2012-07-11 15:12 +1000
    Re: I am still kinda depressed about learning forth quiet_lad <gavcomedy@gmail.com> - 2012-07-10 22:04 -0700
    Re: I am re energized to learn forth and see how simple computers can be! quiet_lad <gavcomedy@gmail.com> - 2012-07-10 22:05 -0700
      Re: I am re energized to learn forth and see how simple computers can be! Mark Wills <markrobertwills@yahoo.co.uk> - 2012-07-11 02:08 -0700
        Re: I am re energized to learn forth and see how simple computers can be! Doug Hoffman <glidedog@gmail.com> - 2012-07-11 07:14 -0400
          Re: I am re energized to learn forth and see how simple computers can be! Mark Wills <markrobertwills@yahoo.co.uk> - 2012-07-11 04:54 -0700
            Re: I am re energized to learn forth and see how simple computers can be! marko <marko@marko.marko> - 2012-07-11 22:30 +1000
            Re: I am re energized to learn forth and see how simple computers can be! Doug Hoffman <glidedog@gmail.com> - 2012-07-11 08:35 -0400
            Re: I am re energized to learn forth and see how simple computers can be! Hannu Vuolasaho <hannu.vuolasaho@nospam.tut.fi.invalid> - 2012-07-11 14:13 +0000
              Re: I am re energized to learn forth and see how simple computers can be! Bernd Paysan <bernd.paysan@gmx.de> - 2012-07-12 22:01 +0200
            Re: I am re energized to learn forth and see how simple computers can be! Fanzo <cristianof6@gmail.com> - 2012-07-11 21:27 +0200
              Re: I am re energized to learn forth and see how simple computers can be! Doug Hoffman <glidedog@gmail.com> - 2012-07-11 16:41 -0400
                Re: I am re energized to learn forth and see how simple computers can be! quiet_lad <gavcomedy@gmail.com> - 2012-07-11 14:49 -0700
              Re: I am re energized to learn forth and see how simple computers can be! Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-12 01:06 +0000
              Re: I am re energized to learn forth and see how simple computers can be! Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-07-13 23:01 -0700
                Re: I am re energized to learn forth and see how simple computers can be! "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-07-14 03:28 -0400
                Re: I am re energized to learn forth and see how simple computers can be! Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-07-14 03:39 -0700
                Re: I am re energized to learn forth and see how simple computers can be! quiet_lad <gavcomedy@gmail.com> - 2012-07-17 15:54 -0700
                Re: I am re energized to learn forth and see how simple computers can be! quiet_lad <gavcomedy@gmail.com> - 2012-07-17 14:23 -0700
            Re: I am re energized to learn forth and see how simple computers can be! Doug Hoffman <glidedog@gmail.com> - 2012-07-11 16:37 -0400
          Re: I am re energized to learn forth and see how simple computers can be! quiet_lad <gavcomedy@gmail.com> - 2012-07-11 13:19 -0700
  Re: I am still kinda depressed about learning forth Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-07-15 16:57 -0700
    Re: I am still kinda depressed about learning forth Clyde Phillips <cwpjr02@gmail.com> - 2012-07-15 22:07 -0700
      Re: I am still kinda depressed about learning forth Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-07-15 22:36 -0700
    Re: I am still kinda depressed about learning forth "WJ" <w_a_x_man@yahoo.com> - 2012-07-17 13:52 +0000
      Re: I am still kinda depressed about learning forth quiet_lad <gavcomedy@gmail.com> - 2012-07-17 16:18 -0700
      Re: I am still kinda depressed about learning forth "WJ" <w_a_x_man@yahoo.com> - 2012-07-18 23:41 +0000
        Re: I am still kinda depressed about learning forth "WJ" <w_a_x_man@yahoo.com> - 2012-07-19 00:34 +0000
          Re: I am still kinda depressed about learning forth Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-07-18 21:11 -0700
            Re: I am still kinda depressed about learning forth "WJ" <w_a_x_man@yahoo.com> - 2012-07-19 06:23 +0000
              Re: I am still kinda depressed about learning forth Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-07-18 23:54 -0700
      Re: I am still kinda depressed about learning forth "WJ" <w_a_x_man@yahoo.com> - 2012-07-19 00:13 +0000
    Re: I am still kinda depressed about learning forth quiet_lad <gavcomedy@gmail.com> - 2012-07-17 16:06 -0700

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