Adding Response spectrum Load case through OAPI matlab to Sap

[Ushaann]

Hi guys,

I am using Matlab2017a to interact with Sap2000. Now that my model is built, i want to add a load case for response spectrum. In the CSi OAPI help documentation, the function to do so is:
SapObject.SapModel.LoadCases.ResponseSpectrum.SetCase

I tried to call the fonction with the following syntax :
LoadCases = NET.explicitCast(SapModel.LoadCases,'SAP2000v18.cLoadCases');
ret = LoadCases.ResponseSpectrum.SetCase('Spec');


It keeps giving me errors that the syntax for this function isn't appropriate:
Error using MatSap (line 357)
No appropriate method, property, or field 'SetCase' for class 'SAP2000v18.wCaseResponseSpectrum'.

Can you help me with the syntax in matlab to Add a load case ?