Re: matrix library?

[Damien Mattei]

yes i will re-implement that from scratch because i can not find
something easy in libraries to use.
I already made it for Racket/Scheme+:
(struct matrix-vect (v)) ;; matrix based on vector of vectors

(define (create-matrix-vect-by-function fct lin col)
  (matrix-vect (create-vector-2d fct lin col)))


;; return the line and column values of dimension
(define (dim-matrix-vect M)

  (when (not (matrix-vect? M))
    (error "argument is not of type matrix"))

  {v <+ (matrix-vect-v M)}
  {lin <+ (vector-length v)}
  {col <+ (vector-length {v[0]})}
  (values lin col))


(define (multiply-matrix-matrix M1 M2)

  {(n1 p1) <+ (dim-matrix-vect M1)}
  {(n2 p2) <+ (dim-matrix-vect M2)}

  (when {p1 ≠ n2} (error "matrix-by-vectors.* : matrix product
impossible, incompatible dimensions"))

  {v1 <+ (matrix-vect-v M1)}
  {v2 <+ (matrix-vect-v M2)}

  (define (res i j)
    (for/sum ([k (in-range p1)])
         {v1[i][k] * v2[k][j]}))

  {v <+ (create-vector-2d res n1 p2)}
  ;(display "v=") (display v) (newline)

  (matrix-vect v))


(define (vector->matrix-column v)
  (matrix-vect (vector-map (lambda (x) (make-vector 1 x))
               v)))

(define (matrix-column->vector Mc)
  {v <+ (matrix-vect-v Mc)}
  (vector-map (lambda (v2) {v2[0]})
          v))

(define (multiply-matrix-vector M v) ;; args: matrix ,vector ;  return vector
  {Mc <+ (vector->matrix-column v)}
  ;(display Mc)
  (matrix-column->vector (multiply-matrix-matrix M Mc)))


 there should be no difference for computation in Guile ,just that i
will use GOOPS instead of struct and that it should be a guile module
written in scheme+ syntax....
see it when finished....


On Wed, Oct 4, 2023 at 8:28 PM <tomas@tuxteam.de> wrote:
>
> On Wed, Oct 04, 2023 at 05:42:10PM +0200, Damien Mattei wrote:
> > thank you. i will try to find a simple example in.
> >
> > On Wed, Oct 4, 2023 at 1:36 PM Nala Ginrut <nalaginrut@gmail.com> wrote:
> > >
> > > And I'd mention AIScm which bound tensorflow APIs. It needs more love.
> > >
> > > https://wedesoft.github.io/aiscm/
> > >
> > >
> > > On Wed, Oct 4, 2023, 17:12 <tomas@tuxteam.de> wrote:
> > >>
> > >> On Wed, Oct 04, 2023 at 08:46:02AM +0200, Damien Mattei wrote:
> > >> > hello,
> > >> > does anyone know if it exists a basic matrix library for Guile?
> > >> > just need to multiply a matrix and a vector.
> > >>
> > >> Perhaps this thread from guile-user [1] has something for you
> > >>
> > >> Cheers
> > >>
> > >> [1] 
> > >> https://lists.gnu.org/archive/html/guile-user/2018-12/threads.html#00117
>
> That all said, if your case doesn't get much hairier,
> it is fairly easy to navigate with Guile's arrays:
>
> (define (dot v1 v2)
>   "The dot product of v1 and v2"
>   (let ((sum 0))
>     (array-for-each
>       (lambda (x1 x2)
>         (set! sum (+ sum (* x1 x2))))
>       v1 v2)
>     sum))
>
> (define (row m i)
>   "The i-th row of m, as a vector"
>   (make-shared-array m (lambda (j) (list i j)) (car (array-dimensions m))))
>
> (define (mat* m v)
>   "Left multiply matrix m and vector v"
>   (let* ((height (cadr (array-dimensions m)))
>          (res (make-typed-array 'f64 0 height)))
>     (do ((i 0 (1+ i)))
>         ((>= i height))
>         (array-set! res (dot (row m i) v) i))
>     res))
>
>
> (define vec #1f64(1 2 1))
> (define mat #2f64((0.5 0.5 0) (0 0.5 0.5) (-0.5 0 0.5)))
>
> (mat* mat vec)
>
>  => (1.5 1.5 0)
>
> CAVEAT: only tested with this one example. Input value checking
> left as an...
>
> Cheers
> --
> t
>