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  • Re: Finding Average without using Recusrion only using Prog

    From B. Pym@21:1/5 to All on Sun Jun 16 04:39:19 2024
    (defun avg (args)
    (loop for x in args
    for l upfrom 1
    summing x into tot
    finally (return (/ tot l))))

    Gauche Scheme

    (use gauche.collection) ;; fold2

    (define (add&count n sum cnt) (values (+ sum n) (+ cnt 1)))

    (define (avg nums)
    (apply /
    (values->list
    (fold2
    add&count
    0 0
    nums))))

    (avg '(20 30 40 50 60 70 80))
    ===>
    50

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  • From HenHanna@21:1/5 to B. Pym on Sun Jun 16 11:28:23 2024
    On 6/15/2024 9:39 PM, B. Pym wrote:
    (defun avg (args)
    (loop for x in args
    for l upfrom 1
    summing x into tot
    finally (return (/ tot l))))

    Gauche Scheme

    (use gauche.collection) ;; fold2

    (define (add&count n sum cnt) (values (+ sum n) (+ cnt 1)))

    (define (avg nums)
    (apply /
    (values->list
    (fold2
    add&count
    0 0
    nums))))

    (avg '(20 30 40 50 60 70 80)) ===> 50


    Nice... Here's a more boring version:


    (define (ave x)
    (let ((L (length x)))
    (if (> L 0)
    (/ (fold + 0 x) L))))

    (define (Pave x) (format #t "~% ~S ~S ~%" x (ave x)))

    (Pave '(1 2 3))
    (Pave '(1 2 3 4))
    (Pave '(1))
    (Pave '())

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    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From HenHanna@21:1/5 to HenHanna on Sun Jun 16 12:48:24 2024
    On 6/16/2024 11:28 AM, HenHanna wrote:
    On 6/15/2024 9:39 PM, B. Pym wrote:
         (defun avg (args)
           (loop for x in args
               for l upfrom 1
               summing x into tot
               finally (return (/ tot l))))

    Gauche Scheme

    (use gauche.collection) ;; fold2

    (define (add&count n sum cnt) (values (+ sum n) (+ cnt 1)))

    (define (avg nums)
       (apply /
         (values->list
           (fold2
             add&count
             0 0
             nums))))

    (avg '(20 30 40 50 60 70 80))     ===>   50


    Nice...    Here's a more boring version:


    (define (ave x)
      (let ((L (length x)))
        (if (> L 0)
          (/ (fold + 0 x) L))))

    (define (Pave x)   (format #t "~%    ~S  ~S  ~%" x (ave x)))

    (Pave  '(1 2 3))
    (Pave  '(1 2 3 4))
    (Pave  '(1))
    (Pave  '())



    (define-macro (ave x)
    `(/ (+ ,@ (map (lambda (n) `(+ ,@ (make-list n 1))) (cadr x)))
    (+ ,@ (map (lambda (n) 1) (cadr x)))))

    (print (ave '(1)))
    (print (ave '(1 2 3)))

    gosh> (macroexpand '(ave '(1 2 3)))
    ==> (/ (+ (+ 1) (+ 1 1) (+ 1 1 1)) (+ 1 1 1))

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  • From Kaz Kylheku@21:1/5 to HenHanna on Mon Jun 17 00:09:20 2024
    On 2024-06-16, HenHanna <HenHanna@devnull.tb> wrote:
    On 6/15/2024 9:39 PM, B. Pym wrote:
    (defun avg (args)
    (loop for x in args
    for l upfrom 1
    summing x into tot
    finally (return (/ tot l))))

    Gauche Scheme

    (use gauche.collection) ;; fold2

    (define (add&count n sum cnt) (values (+ sum n) (+ cnt 1)))

    (define (avg nums)
    (apply /
    (values->list
    (fold2
    add&count
    0 0
    nums))))

    (avg '(20 30 40 50 60 70 80)) ===> 50


    Nice... Here's a more boring version:


    (define (ave x)
    (let ((L (length x)))
    (if (> L 0)
    (/ (fold + 0 x) L))))

    (define (Pave x) (format #t "~% ~S ~S ~%" x (ave x)))

    (Pave '(1 2 3))
    (Pave '(1 2 3 4))
    (Pave '(1))
    (Pave '())

    This is the TXR Lisp interactive listener of TXR 294.
    Quit with :quit or Ctrl-D on an empty line. Ctrl-X ? for cheatsheet.
    Evidence of amphoric Lisp macros was recently found in ancient clay
    jars.
    [[callf / sum len] '(1 2 3 4)]
    2.5

    callf: return a function which:

    - applies the second and subsequent functions given to callf (here sum
    and len) to its arguments.
    - applies the first argument of callf (here /) to the resulting
    values.
    - returns the resulting value

    --
    TXR Programming Language: http://nongnu.org/txr
    Cygnal: Cygwin Native Application Library: http://kylheku.com/cygnal
    Mastodon: @Kazinator@mstdn.ca

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  • From Kaz Kylheku@21:1/5 to steve g on Fri Aug 9 23:30:54 2024
    On 2024-08-09, steve g <sgonedes1977@gmail.com> wrote:
    "B. Pym" <No_spamming@noWhere_7073.org> writes:

    < > (defun avg (args)
    < > (loop for x in args
    < > for l upfrom 1
    < > summing x into tot
    < > finally (return (/ tot l))))





    Gauche Scheme

    (use gauche.collection) ;; fold2

    (define (add&count n sum cnt) (values (+ sum n) (+ cnt 1)))

    (define (avg nums)
    (apply /
    (values->list
    (fold2
    add&count
    0 0
    nums))))

    (avg '(20 30 40 50 60 70 80))
    ===>
    50


    (loop for x in '(1 2 3 4 5)
    summing x into max
    counting x into cnt
    finally (pprint (/ max cnt)))

    [[callf / sum len] '(1 2 3 4 5)]
    3.0

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