(use-modules (system foreign)
             (system foreign-library))

(define libgsl
  (load-foreign-library "/gnu/store/zfxs8xbh68nb8smvsdf9i6aj6hbzgix4-profile/lib/libgsl.so"))

(define gsl-vector-alloc
  (foreign-library-function libgsl
                            "gsl_vector_alloc"
                            #:return-type '*
                            #:arg-types (list size_t)))

(define gsl-vector-set
  (foreign-library-function libgsl
                            "gsl_vector_set"
                            #:return-type void
                            #:arg-types (list '* size_t double)))

(define gsl-vector-get
  (foreign-library-function libgsl
                            "gsl_vector_get"
                            #:return-type double
                            #:arg-types (list '* size_t)))

(define gsl-blas-dscal
  (foreign-library-function libgsl
                            "gsl_blas_dscal"
                            #:return-type void
                            #:arg-types (list double '*)))

(let* ((n 3)
       (x (gsl-vector-alloc n)))
  (for-each (lambda (i)
              (gsl-vector-set x i i))
            (iota n))
  (gsl-blas-dscal 10 x))