Excel-VBA中的简单移动平均范围

Question

This code is just to calculate simple moving average. Opened an excel, created dummy array in C row from 1 to 20. I want to create a function for eg: SMA(C7,3) = which should give average of C5:C7.

Coming back to VBA after long time, not able to figure whats the error in the below code.

Function sma1(rng As Range, N As Integer)
Set rng = rng.Resize(-N + 1, 0)
sma1 = Application.WorksheetFunction.average(rng)
End Function

Answer 1

1. avoid using a cell name as a function
2. fixed the RESIZE()
3. used an internal range variable

Function smal(rng As Range, N As Integer) As Variant Dim rng2 As Range Set rng2 = rng.Resize(N, 1) smal = Application.WorksheetFunction.Average(rng2) End Function

EDIT#1:

Based on Scott's comment:

Function smal(rng As Range, N As Integer) As Variant
    Dim rng2 As Range
    Set rng2 = rng.Offset(1 - N, 0).Resize(N, 1)
    smal = Application.WorksheetFunction.Average(rng2)
End Function

Answer 2

I assume you want the column along side it to give you're SMA (as shown below?):

If so, the below will do it and drag it autocomplete it to the bottom of you column C array:

Sub SMA3()
    Range("D7").FormulaR1C1 = "=AVERAGE(R[-2]C[-1]:RC[-1])" 'This is a relative reference (left one cell and up two cells) - This give your three inputs
    Range("D7").AutoFill Destination:=Range("D7:D" & Range("C1048576").End(xlUp).Row) 'Autofills the SMA
End Sub

Answer 3

Just an FYI this can be done with existing formula:

=IF(ROW(C1)<$E$1,"",AVERAGE(INDEX(C:C,ROW(C1)-$E$1+1):C1))

E1 contains the number of rows to include.