# cfamily: Ridge Chaining Procedure In Rwave: Time-Frequency Analysis of 1-D Signals

 cfamily R Documentation

## Ridge Chaining Procedure

### Description

Chains the ridge estimates produced by the function `crc`.

### Usage

```cfamily(ccridge, bstep=1, nbchain=100, ptile=0.05)
```

### Arguments

 `ccridge` unchained ridge set as the output of the function `crc` `bstep` maximal length for a gap in a ridge. `nbchain` maximal number of chains produced by the function. `ptile` relative threshold for the ridges.

### Details

`crc` returns a measure in time-frequency (or time-scale) space. `cfamily` turns it into a series of one-dimensional objects (ridges). The measure is first thresholded, with a relative threshold value set to the input parameter ptile. During the chaining procedure, gaps within a given ridge are allowed and filled in. The maximal length of such gaps is the input parameter bstep.

### Value

Returns the results of the chaining algorithm

 `ordered map` image containing the ridges (displayed with different colors) `chain` 2D array containing the chained ridges, according to the chain data structure chain[,1]: first point of the ridge chain[,2]: length of the chain chain[,3:(chain[,2]+2)]: values of the ridge `nbchain` number of chains produced by the algorithm

### References

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

`crc` for the ridge estimation, and `crcrec`, `gcrcrec` and `scrcrec` for corresponding reconstruction functions.

### Examples

```
## Not run:
data(HOWAREYOU)
plot.ts(HOWAREYOU)

cgtHOWAREYOU <- cgt(HOWAREYOU,70,0.01,100)

clHOWAREYOU <- crc(Mod(cgtHOWAREYOU),nbclimb=1000)

cfHOWAREYOU <- cfamily(clHOWAREYOU,ptile=0.001)
image(cfHOWAREYOU\$ordered > 0)

## End(Not run)
```

Rwave documentation built on Oct. 22, 2022, 1:05 a.m.