IBM® SPSS® Amos™ 28

The following program fits the model of Example 8. It then displays two matrices: 1) the matrix of approximate second derivatives, and 2) two times the inverse of the matrix of approximate second derivatives.

Module MainModule
    ' Evaluate2a and EvaluateEx2a methods example
    Sub Main()
        Dim Sem As New AmosEngineLib.AmosEngine
        Dim ad As New AmosDebug.AmosDebug
        Dim Originalparameters() As Double
        Sem.Covest()
 
        Sem.BeginGroup(AmosEngine.AmosDir & "Examples\English\UserGuide.xls", "Grnt_fem")
        Sem.AStructure("visperc = (1) spatial + (1) err_v")
        Sem.AStructure("cubes = (a) spatial + (1) err_c")
        Sem.AStructure("lozenges = (b) spatial + (1) err_l")
        Sem.AStructure("paragraph = (1) verbal + (1) err_p")
        Sem.AStructure("sentence = (c) verbal + (1) err_s")
        Sem.AStructure("wordmean = (d) verbal + (1) err_w")
 
        If (Sem.FitModel() = 0) Then
            Dim Ind As Integer
            Dim F As Double
            Dim G() As Double
            Dim H() As Double
            Dim HI() As Double
    
            Sem.Evaluate2a(Ind, F, G, H)
    
            If Ind = 0 Then
                ad.PrintTriangle(H, "Approximate 2nd derivatives")
            Else
                ad.PrintX("Approximate 2nd derivatives could not be calculated.")
            End If
 
            Sem.EvaluateEx2a(Ind, F, G, HI)
 
            If Ind = 0 Then
                If Sem.WasInverted Then
                    ad.PrintTriangle(HI, "Approximate 2nd derivatives inverted (times 2)")
                Else
                    ad.PrintX("Matrix of 2nd derivatives could not be inverted.")
                End If
            End If
        End If
 
        Sem.Dispose()
    End Sub
End Module