R: condno

condno {adlift} | R Documentation

## condno

### Description

This function uses a specified norm to compute the condition number of a matrix representation of a wavelet transform.

### Usage

    condno(W, type)

### Arguments

`W` | a matrix which represents a wavelet transform.
`type` | a character string denoting which norm to use when computing the condition number. Possible values are "l1", or one of the standard norm types, "F" (Frobenius norm), "i" (infinity norm), "m" (max modulus of a matrix) or "1" (1-norm).

### Details

The function computes the condition number as condno = ||W||*||W^{-1}||.

### Value

`condno` | the condition number of the matrix W.

### Note

The matrix W must be invertible.

### Author(s)

Matt Nunes (nunesrpackages@gmail.com), Marina Knight

### Examples

    #create test signal data
    #
    x<-runif(100)
    y<-make.signal2("blocks",x=x)
    #
    a<-fwtnp(x,y,LocalPred=AdaptNeigh,neigh=2,do.W=TRUE,varonly=FALSE)
    #
    #computes the transition matrix for the specified options
    #
    W<-a$W
    #
    condno(W,"F")
    #
    condno(W,"l1")
    #
    condno(W,"1")
    #

[Package adlift version 1.4-1 Index]