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Task/Averages-Simple-moving-average/Nim/averages-simple-moving-average.nim

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+import queues
+
+proc simplemovingaverage(period: int): auto =
+  assert period > 0
+
+  var
+    summ, n = 0.0
+    values = initQueue[float]()
+  for i in 1..period:
+    values.add(0)
+
+  proc sma(x: float): float =
+    values.add(x)
+    summ += x - values.dequeue()
+    n = min(n+1, float(period))
+    result = summ / n
+
+  return sma
+
+var sma = simplemovingaverage(3)
+for i in 1..5: echo sma(float(i))
+for i in countdown(5,1): echo sma(float(i))
+
+echo ""
+
+var sma2 = simplemovingaverage(5)
+for i in 1..5: echo sma2(float(i))
+for i in countdown(5,1): echo sma2(float(i))