.BG
.FN corona
.TL
Ridge Estimation by Corona Method
.DN
Estimate a (single) ridge from a time-frequency representation, using the
corona method.
.CS
corona(tfrep, guess, tfspec=numeric(dim(tfrep)[2]), subrate=1, temprate=3, mu=1, lambda=2 * mu, iteration=1000000, seed=-7, stagnant=20000, costsub=1, plot=T)
.RA
.AG tfrep
Time-Frequency representation (real valued).
.AG guess
Initial guess for the algorithm.
.OA
.AG tfspec
Estimate for the contribution of the noise to modulus.
.AG subrate
Subsampling rate for ridge estimation.
.AG temprate
Initial value of temperature parameter.
.AG mu
Coefficient of the ridge's second derivative in cost function.
.AG lambda
Coefficient of the ridge's derivative in cost function.
.AG iteration
Maximal number of moves.
.AG seed
Initialization of random number generator.
.AG stagnant
Maximum number of stationary iterations before stopping.
.AG costsub
Subsampling of cost function in output.
.AG plot
When set(default), some results will be shown on the display.
.RT
Returns the estimated ridge and the cost function.

ridge: 1D array (of same length as the signal) containing the
ridge.

cost: 1D array containing the cost function. 
.SE
.DT
To accelerate convergence, it is useful to preprocess
modulus before running annealing method. Such a
preprocessing (smoothing and subsampling of modulus)
is implemented in "corona". The parameter subrate
specifies the subsampling rate.
.SH REFERENCES
See discussion in text of "Practical Time-Frequency Analysis".
.SA
"icm","coronoid","snake", "snakoid".
.SH WARNING
The returned cost may be a large array, which is time consuming.
The argument costsub allows subsampling the cost function.
.EX
