Data commit

Task/Averages-Simple-moving-average/Racket/averages-simple-moving-average.rkt

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+#lang racket
+
+(require data/queue)
+
+(define (simple-moving-average period)
+  (define queue (make-queue))
+  (define sum 0.0)
+
+  (lambda (x)
+    (enqueue! queue x)
+    (set! sum (+ sum x))
+    (when (> (queue-length queue) period)
+      (set! sum (- sum (dequeue! queue))))
+    (/ sum (queue-length queue))))
+
+;; Tests
+(define sma3 (simple-moving-average 3))
+(define sma5 (simple-moving-average 5))
+(for/lists (lst1 lst2)
+           ([i '(1 2 3 4 5 5 4 3 2 1)])
+  (values (sma3 i) (sma5 i)))