You must first make an instance of an object before you can use it.
In your case, yoiu actually need to instantiate 2 objects before you can attempt to use them (your tvret - which would be an instance of the TVReturn class, and its member amortization - which is an instance of a instance TVAmortizationSchedule class). You'll also need a way to make an instance of TVAmortizationData and put it into the "data" array that you are apparently trying to use as the only member of your TVAmortization class. You'll need a way to dimension the "data" array as well... or at least I think you will. Does this code compile? Apparently it does, but you have a little work to do before this will actually do anything.
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