R: Ridge Estimation by ICM Method

icm {Rwave} | R Documentation

## Ridge Estimation by ICM Method

### Description

Estimate a (single) ridge from a time-frequency representation, using the ICM minimization method.

### Usage

    icm(modulus, guess, tfspec=numeric(dim(modulus)[2]), subrate=1,
    mu=1, lambda=2 * mu, iteration=100)

### Arguments

`modulus` | Time-Frequency representation (real valued).
`guess` | Initial guess for the algorithm.
`tfspec` | Estimate for the contribution of the noise to modulus.
`subrate` | Subsampling rate for ridge estimation.
`mu` | Coefficient of the ridge's second derivative in cost function.
`lambda` | Coefficient of the ridge's derivative in cost function.
`iteration` | Maximal number of moves.

### Details

To accelerate convergence, it is useful to preprocess modulus before running annealing method. Such a preprocessing (smoothing and subsampling of modulus) is implemented in `icm`. The parameter subrate specifies the subsampling rate.

### Value

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.

### References

See discussions in the text of “Practical Time-Frequency Analysis”.

### See Also

`corona`, `coronoid`, and `snake`, `snakoid`.

[Package Rwave version 2.6-0 Index]