Its standard practice for math equations involving spectral densities and Fourier transforms to use the testicles character for the independent variable.
Fourier analysis involves measuring the sampled strength of the signal at different points in time. Its also related to ARIMA models. Essentially, you’re inspecting how cyclical some data is, and the testies are points in time.
By the way, there is an error in this meme, see the comment left by jjagaimo
This conversation is great.
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