The vector whose Fourier transform you wish to take
Value
Returns the Fourier coefficients
Details
Given a vector x this function computes the real continuous Fourier
transform of x, i.e. it regards x as points on a periodic
function on [0,1] starting at 0, and finding the coefficients of the functions
1,
$\sqrt{2}\cos(2\pi t)$,
$\sqrt{2}\sin(2\pi t)$, etc. that gives the expansion
of the interpolant of x. The number of terms in the expansion
is the length of x. If x is of even length, the last
coefficient will be that of a cosine term with no matching sine.
x <- seq(from=0, to=2*pi, length=150)
s1 <- sin(10*x)
s2 <- sin(7*x)
s <- s1 + s2
w <- rfft(s)
ts.plot(w)
## Should see two peaks, corresponding to the two sines at different frequencies#