Estimate a ridge from a time-frequency representation, using the snake method.
snake(tfrep, guessA, guessB, snakesize=length(guessB),
tfspec=numeric(dim(modulus)[2]), subrate=1, temprate=3, muA=1,
muB=muA, lambdaB=2 * muB, lambdaA=2 * muA, iteration=1000000,
seed=-7, costsub=1, stagnant=20000, plot=TRUE)Time-Frequency representation (real valued).
Initial guess for the algorithm (frequency variable).
Initial guess for the algorithm (time variable).
the length of the initial guess of time variable.
Estimate for the contribution of the noise to modulus.
Subsampling rate for ridge estimation.
Initial value of temperature parameter.
Coefficient of the ridge's derivative in cost function (frequency component).
Coefficient of the ridge's derivative in cost function (time component).
Coefficient of the ridge's second derivative in cost function (time component).
Coefficient of the ridge's second derivative in cost function (frequency component).
Maximal number of moves.
Initialization of random number generator.
Subsampling of cost function in output.
maximum number of steps without move (for the stopping criterion)
when set (by default), certain results will be displayed
Returns a structure containing:
1D array (of same length as the signal) containing the ridge.
1D array containing the cost function.
See discussions in the text of “Practical Time-Frequency Analysis”.