nlevels.default {wavethresh} | R Documentation

## Returns number of levels associated with an object

### Description

This function returns the number of scale levels associated with either a wavelet type object or an atomic object.

### Usage

    nlevels.default(object, ...)

### Arguments

`object` | An object for which you wish to determine how many levels it has or is associated with.
`...` | any other arguments

### Details

This function first checks to see whether the input object has a component called nlevels. If it does then it returns the value of this component. If it does not then it takes the length of the object and then uses the `IsPowerOfTwo` function to return the power of two which equals the length (if any) or NA if the length of the object is not a power of two.

### Value

The number of resolution (scale) levels associated with the object.

### Author(s)

Version 3.6.0 Copyright Guy Nason 1995

### See Also

`nlevels`

### Examples

    #
    # Generate some test data
    #
    #test.data <- example.1()$y
    #
    # Now, this vector is 512 elements long. What number of levels would any
    # wavelet object be that was associated with this vector?
    #
    #nlevels(test.data)
    # [1] 9
    #
    # I.e. 2^9=512. Let's check by taking the wavelet transform of the
    # test data and seeing how many levels it actually has
    #
    #nlevels(wd(test.data))
    # [1] 9

[Package wavethresh version 4.0-2 Index]