cwtpolar {Rwave}

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 \times noctave \times 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 \times nb_scales)

3D array (signal size \times noctave \times 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)