Hit the reset button to get some starter code. The starter code has five variables you can uncomment, prettify, and define. If you define the getSample function, that's what will be used to generate your wavetable. Otherwise, your wavetable will be generated additively using the getPhase and getAmplitude functions. If you don't define anything, you'll get an additively-generated table with zero-phase and saw-wave-amplitude harmonics by default.
You can limit the number of tables to be generated using the numberOfFrames variable (great for making it go faster when you only need one frame), and if you're generating your wavetable additively you can change the number of harmonics to generate using the numberOfHarmonics variable.