R: Conversion to Polar Coordinates

cwtpolar {Rwave} | R Documentation

## Conversion to Polar Coordinates

### Description

Converts one of the possible outputs of the function `cwt` to modulus and phase.

### Usage

    cwtpolar(cwt, threshold=0)

### Arguments

`cwt` | 3D array containing the values of a continuous wavelet transform in the format (signal size x noctave x nvoice) as in the output of the function `cwt` with the logical flag `twodimension` set to FALSE.
`threshold` | value of a level for the absolute value of the modulus below which the value of the argument of the output is set to -pi.

### Details

The output contains the (complex) values of the wavelet transform of the input signal. The format of the output can be

2D array (signal size x nb\_scales)

3D array (signal size x noctave x nvoice)

### Value

Modulus and Argument of the values of the continuous wavelet transform

`output1` | 3D array giving the values (in the same format as the input) of the modulus of the input.
`output2` | 3D array giving the values of the argument of the input.

### References

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

### See Also

`cwt`, `DOG`, `cwtimage`.

### Examples

        x <- 1:512
        chirp <- sin(2*pi * (x + 0.002 * (x-256)^2 ) / 16)
        retChirp <- cwt(chirp, noctave=5, nvoice=12, twoD=FALSE, plot=FALSE)
        retPolar <- cwtpolar(retChirp)

[Package Rwave version 2.5-0 Index]