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Task/Averages-Arithmetic-mean/FreeBASIC/averages-arithmetic-mean.freebasic

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+' FB 1.05.0 Win64
+
+Function Mean(array() As Double) As Double
+  Dim length As Integer = Ubound(array) - Lbound(array) + 1
+  If length = 0 Then
+    Return 0.0/0.0 'NaN
+  End If
+  Dim As Double sum = 0.0
+  For i As Integer = LBound(array) To UBound(array)
+    sum += array(i)
+  Next
+  Return sum/length
+End Function
+
+Function IsNaN(number As Double) As Boolean
+  Return Str(number) = "-1.#IND" ' NaN as a string in FB
+End Function
+
+Dim As Integer n, i
+Dim As Double num
+Print "Sample input and output"
+Print
+Do
+  Input "How many numbers are to be input ? : ", n
+Loop Until n > 0
+Dim vector(1 To N) As Double
+Print
+For i = 1 to n
+  Print "  Number #"; i; " : ";
+  Input "", vector(i)
+Next
+Print
+Print "Mean is"; Mean(vector())
+Print
+Erase vector
+num = Mean(vector())
+If IsNaN(num) Then
+  Print "After clearing the vector, the mean is 'NaN'"
+End If
+Print
+Print "Press any key to quit the program"
+Sleep