fastwhiten: Simple fastwhitening function.
In stnava/itkImageR: Examples using Rcpp to interface R and ITK

Description Usage Arguments Value Author(s) Examples

whitens the input matrix using a fast SVD and returns the result. can select number of principal components to use. might want to scale the matrix before input.

1	wmat<-fastwhiten( mat , 50 )

mat

input matrix

matrix is output

Avants BB

mat<-replicate(400, rnorm(600)) 
print(mean(abs(cor(mat))))
wmat<-fastwhiten( scale( mat ) ) 
print(mean(abs(cor(wmat))))
wmat<-fastwhiten( scale( mat ), 20 ) 
print(mean(abs(cor(wmat))))