Verify code on MATLAB using Duhmel's integral and preform parametric analysis.

I have done coding on MATLAB to create a response spectrum to an earthquake situation. I require someone to verify my coding using Duhamel's integral. A parametric analysis should be preformed using the algorithm. Different response spectrum's should also be created using different damping ratio's - showing how the structure may behave with different damping values (during earthquake) A DETAILED discussion should also be provided, explaing each step.