# R/finiteImpulseResponseDesignMatrix.R In stnava/RKRNS: ANTsR Decoding

#### Documented in finiteImpulseResponseDesignMatrix

```#' Simple finiteImpulseResponseDesignMatrix function.
#'
#' Convert a design matrix (or any matrix) to a time-shifted version of itself
#' as needed by finite impulse response models used when deconvolving
#' hemodynamic response functions.
#'
#'
#' @param mat input matrix
#' @param n shift amount
#' @param baseshift baseline shift amount so total shift is n+baseshift
#' @return matrix is output
#' @author Avants BB
#' @examples
#'
#' mat<-diag(10)
#' wmat<-finiteImpulseResponseDesignMatrix( mat , 5 )
#'
finiteImpulseResponseDesignMatrix <- function(x,n=1,baseshift=0) {
if (nargs() == 0) {
print( args( finiteImpulseResponseDesignMatrix ) )
return(1)
}
nc<-ncol(x)
nr<-nrow(x)
xi<-matrix( rep(0,nr*nc*n), nrow=nr )
colnames(xi)<-paste("V",1:ncol(xi))
colnamesxi<-colnames(xi)
colnamesx<-colnames(x)
j<-1
for ( i in 1:ncol(x) )
{
basecol<-shift(x[,i],baseshift)
shiftmat<-basecol
for ( k in 2:n ) shiftmat<-cbind(shiftmat,shift(basecol,k-1))
xi[,j:(j+n-1)]<-shiftmat
colnamesxi[j:(j+n-1)]<-paste(colnamesx[i],1:n,sep='')
j<-j+n
}
colnames(xi)<-colnamesxi
return(xi)
}
```
stnava/RKRNS documentation built on Aug. 26, 2017, 9:55 a.m.