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HW4 #5 A
ScalarProductDoLoop.rkt by Ryan Liszewski
Calculates the scalar product of the given 2 vectors using a do loop
produces an error message when the vectors have different lengths or is empty
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#lang racket
(define scalar-product
  (lambda (x y)
    (cond((= (vector-length x) (vector-length y))
           (let ((z 0))
                  (do ((i 0 (add1 i)))
                    ((>= i (vector-length x)) (display z))
                    (set! z
                          (+ z (* (vector-ref x i) (vector-ref y i)))))))
          (else (display "Error: different sizes of vectors!")))))


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HW4 #5 B
ScalarProductRecursive.rkt by Ryan Liszewski
Calculates the scalar product of the given 2 vectors using recursion
produces an error message when the vectors have different lengths
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#lang racket
(define scalar-product
  (lambda (x y)
    ;If they equal the same size
    (cond ((= (vector-length x) (vector-length y))
            ;FInd scalar product
           (recur (vector->list x) (vector->list y)))
           ;else the size are not the same
          (else (display "Error: different sizes of vectors!")))))
;Calls function recursively
(define recur
    (lambda (list1 list2)
      (cond ((null? (cdr list1)) (* (car list1) (car list2)))
            (else (+ (* (car list1) (car list2))
                     (recur (cdr list1) (cdr list2)))))))