dopp {CVThresh} | R Documentation |
This function generates Doppler function values for n equally spaced points in [0,1].
dopp(norx=1024)
norx |
the number of data or x values in [0, 1] |
Doppler function is introduced by Donoho and Johnstone (1994) and is useful test function evaluating a wavelet shrinkage method.
Doppler function values f(i/n), i=1,...,n and its variability ||f|| = sum_{i=1}^n (f_i - mena(f))^2 / (n-1) where mena(f) = sum_{i=1}^n f_i / n.
Donoho, D.L. and Johnstone, I.M. (1994) Ideal spatial adaptation by wavelet shrinkage. Biometrika, 81, 425–455.
testdopp <- dopp(1024) plot(testdopp$x, testdopp$meanf, xlab="", ylab="", main="Plot of Doppler function", type="l")