What is fft butterfly diagram?

The FFT (Fast Fourier Transform) butterfly diagram is a tool used to visualize the process of computing the FFT algorithm. The FFT algorithm is used to transform time-domain data into the frequency-domain, allowing analysis of the spectral content of the signal. The butterfly diagram shows the computations performed during this transform process, where data is divided into smaller subcomponents and recombined to give the final frequency-domain representation. The butterfly diagram consists of multiple stages, each representing the computations performed at different levels of detail, and the data flow between the stages. The name "butterfly" comes from the shape of the connections between the various stages, with arrows that resemble the wings of a butterfly. Understanding the butterfly diagram is important when implementing and optimizing FFT algorithms as it allows for visualizing the computational complexity involved in the process.