Is matlab fft faster for real input?

1. Is the FFT of a real signal real?
2. What makes the FFT fast?
3. What are the disadvantages of FFT?
4. How much faster is FFT?

Is the FFT of a real signal real?

Most real-world signals are real-valued. Therefore, you can use the real fast Fourier transform (FFT) for most applications. You also can use the complex FFT by setting the imaginary part of the signal to zero.

What makes the FFT fast?

the easiest way to understand why its faster is because FFT uses both cos+sin on the other hand DFT only uses cos, DFT is more common because it requires less space in compression in general for image, sound,... the other comments are do a deep dive, mine is just a taste of the stuff.

What are the disadvantages of FFT?

A disadvantage associated with the FFT is the restricted range of waveform data that can be transformed and the need to apply a window weighting function (to be defined) to the waveform to compensate for spectral leakage (also to be defined). An alternative to the FFT is the discrete Fourier transform (DFT).

How much faster is FFT?

Graphical explanation for the speed of the Fast Fourier Transform. For a sample set of 1024 values, the FFT is 102.4 times faster than the discrete Fourier transform (DFT). The basis for this remarkable speed advantage is the `bit-reversal' scheme of the Cooley-Tukey algorithm.