最小二乗法　1次

VBA

Option Explicit
Sub aaaa()
    
    Dim lngArry() As Variant
    ReDim lngArry(9) As Variant
    
    Dim i As Long
    For i = 0 To 9
        lngArry(i) = i
    Next i
    
    For i = 0 To 20
    Debug.Print GetYosoku(lngArry, i)
    Next i
    
End Sub
Function GetYosoku(dblArry() As Variant, n As Long) As Double
    
    Dim dblA As Double
    Dim dblB As Double
    Dim dblC As Double
    Dim dblD As Double
    Dim dblE As Double
    Dim dblf As Double
    Dim dblg As Double
    Dim lngN As Long
    Dim i As Long
    
    lngN = UBound(dblArry) - LBound(dblArry) + 1
    For i = LBound(dblArry) To UBound(dblArry)
        dblA = dblA + dblArry(i) ^ 2
        dblB = dblB + (i - LBound(dblArry) + 1) ^ 2
        dblC = dblC + dblArry(i)
        dblD = dblD + (i - LBound(dblArry) + 1) * dblArry(i)
        dblE = dblE + (i - LBound(dblArry) + 1)
    Next i
    
    dblf = (lngN * dblD - dblC * dblE) / (lngN * dblB - dblE ^ 2)
    dblg = (dblB * dblC - dblD * dblE) / (lngN * dblB - dblE * dblE)
    GetYosoku = dblf * (n + 1) + dblg
    
End Function