A
twiddle factor, in fast Fourier transform (FFT) algorithms, is any of the trigonometric constant coefficients that are multiplied by the
Kaynak: Twiddle factorof size r (performed m times on corresponding outputs of the sub-transforms) pre-multiplied by roots of unity (known as
twiddle factor s
Kaynak: Butterfly diagramand N 2, along with O(N) multiplications by complex roots of unity traditionally called
twiddle factor s (after Gentleman and Sande, 1966).
Kaynak: Fast Fourier transformthe disadvantage that it also requires extra multiplications by roots of unity called
twiddle factor s, in addition to the smaller transforms.
Kaynak: Prime-factor FFT algorithmThe phase factor exp-2pi i k/ N (called a
twiddle factor ) obeys the relation: exp-2pi i (k + N/2)/ N e^-pi i exp-2pi i k/ N -exp-
Kaynak: Cooley–Tukey FFT algorithmalgorithms, where the same trigonometric function values (called
twiddle factors) must be evaluated many times in a given transform,
Kaynak: Trigonometric tables