No, from within a tool, I want to create a function that will return the fundamental and harmonic frequencies of a sample. For example in this tool i could use it to do better pitch detection.
Yes, code examples would be awesome 
I tried using the example code that comes with Lua FFT but the output didn’t really make much sense to me. I want to be able to test it with a sine wave and see the fundamental frequency but the example code didn’t let me do this, any help is great.
Cheers