ChordRef.scm

(define A 1)
(define B 2)
(define C 3)
(define D 4)
(define E 5)
(define F 6)
(define G 7)
(define sharp-wheel (list F C G D A E B))
(define flat-wheel (list B E A D G C F))
(define get-note-name
  (lambda (note)
    (case note
      ((A) "A")
      ((B) "B")
      ((C) "C")
      ((D) "D")
      ((E) "E")
      ((F) "F")
      ((G) "G"))))

(define range
  (lambda (n m)
    (if (<= n m)
    (range_h n (- m 1) '())
    (reverse (range_h (+ m 1) n '())))))

(define range_h
  (lambda (n m xs)
    (if (= n m)
    (cons m xs)
    (range_h n (- m 1) (cons m xs)))))

(define get-accidents
  (lambda (n xs)
    (if (= n 0)
    (list (car xs))
    (cons (car xs) (get-accidents (- n 1) (cdr xs))))))

(define num-sharps
  (lambda (key)
    (modulo (+ (* key 2) 1) 7)))

(define num-flats
  (lambda (key)
    (case key
      ((A) 4)
      ((B) 2)
      ((C) 0)
      ((D) 5)
      ((E) 3)
      ((F) 1)
      ((G) 6))))