How can I display the contents of a structure returned by my MATLAB Builder EX component in Excel?

I have a MATLAB function that returns a structure. I have built this function into an Excel Add-in and I now wish to display the contents of the structure in an Excel worksheet.

My MATLAB function returnOutputStruct returns a structure with two fields, each of which contains a 24 x 1 double matrix. After importing the BAS file generated by the Builder EX, I select a 24 x 2 range of cells in my worksheet and call the function returnOutputStruct. When I do this, I get the following error

 Error in VBAProject: Subscript out of Range

Answer 1

[MathWorks Support Team]

You can work around this issue by using the MWStruct API. Since the MATLAB component returns a MWStruct, you can use the methods and properties of this class to extract the data of the structure into an VBA Array. As an example, you can edit the VBA code to read like:

Function returnOutputStruct(Optional in1 As Variant, Optional in2 As Variant) As Variant

      Dim outStruct As Variant

      On Error GoTo Handle_Error

      Call InitModule

      If outputStructureDemo Is Nothing Then

          Set outputStructureDemo = CreateObject("StructureDemo.outputStructureDemo.1_0")

      End If

      Call outputStructureDemo.returnOutputStruct(1, outStruct, in1, in2)

      '-----------------------Changes begin here----------------------------------

      'Use the Item method to extract each field into a Variant

Dim col1 As Variant

      Dim col2 As Variant

      col1 = outStruct.Item(1, "field1")

      col2 = outStruct.Item(1, "field2")

'Iterate through the fields to extract each element of each field into an Array

      Dim outArray(1 To 24, 1 To 2)

      Dim i As Integer

      For i = 1 To 24

          outArray(i, 1) = col1(i, 1)

          outArray(i, 2) = col2(i, 1)

      Next i

      returnOutputStruct = outArray

      '-----------------------Changes end here----------------------------------

      Exit Function

Handle_Error:

      returnOutputStruct = "Error in " & Err.Source & ": " & Err.Description

End Function