I am trying to determine if one can calculate a frame rate using the NVidia API (NVAPI). I am not sure how tools such as dxtory and fraps are providing this measure, but I was wondering it was possible to derive frame rate from nvapi.That is a nearly 5 year old article, much has changed since then. What are you trying to figure out?
https://www.tomshardware.com/reviews/graphics-performance-myths-debunked,3739.html