VBA Matrix Operations Help Needed.

[dennygibson]

Hi … here's a snippet from a macro I'm working on … I can't get the last statement (multiply a matrix by the inverse of another matrix) Everything else works but the last statement:

Option Explicit
Option Base 1
Sub Coefficients()
Dim C() As Variant
Dim D() As Variant
Dim F() As Variant 
ReDim C(1 To 2, 1 To 2)
ReDim D(1 To 2, 1 To 1)
ReDim F(1 To 2, 1 To 1)
ReDim Cinv(1 To 2, 1 To 2)
'Set initial conditions
        W1 = 0
        Del1 = 0.05
'    Swirl Chamber Coefficient Assembly
        C(1, 1) = Del1 * W1
        C(1, 2) = Del1 ^ 2
        C(2, 1) = ((A2 - B2) * Del1 * W1 ^ 2)
        C(2, 2) = ((A2 - 2 * B2 + 1) * Del1 ^ 2 * W1)
        D(1, 1) = B1 / A1
        D(2, 1) = C2 * W1
        ActiveSheet.Range("T5") = C(1, 1)
        ActiveSheet.Range("U5") = C(1, 2)
        ActiveSheet.Range("T6") = C(2, 1)
        ActiveSheet.Range("U6") = C(2, 2)
        ActiveSheet.Range("X5") = D(1, 1)
        ActiveSheet.Range("X6") = D(2, 1)
'    Get F
'    Note: we have {C}dx/dt={D} ... need: dx/dt={F}=[C_inverse]{D}
        F = WorksheetFunction.MMult(WorksheetFunction.MInverse(C), D) --- this is the statement that bombs!!!
End Sub