BayesfMRI (version 0.3.11)

is.BfMRI.sess: Validate a "BfMRI.sess" object.

Description

Check if object is valid for a "BfMRI.sess" object.

Usage

is.BfMRI.sess(x)

Value

Logical. Is x a valid "BfMRI.sess" object?

Arguments

x

The putative "BfMRI.sess" object.

Details

A "BfMRI.sess" object is a list of length \(S\), where \(S\) is the number of sessions in the analysis. Each list entry corresponds to a separate session, and should itself be a list with these named fields:

BOLD

a \(T \times V\) BOLD matrix. Rows are time points; columns are data locations (vertices/voxels).

design

a \(T \times K\) matrix containing the \(K\) task regressors. See make_HRFs.

nuisance

an optional argument. \(T \times J\) matrix containing the \(L\) nuisance regressors.

In addition, all sessions must have the same number of data locations, \(V\), and tasks, \(K\).

Examples

nT <- 180
nV <- 700 
BOLD1 <- matrix(rnorm(nT*nV), nrow=nT)
BOLD2 <- matrix(rnorm(nT*nV), nrow=nT)
onsets1 <- list(taskA=cbind(c(2,17,23),4)) # one task, 3 four sec-long stimuli
onsets2 <- list(taskA=cbind(c(1,18,25),4))
TR <- .72 # .72 seconds per volume, or (1/.72) Hz
duration <- nT # session is 180 volumes long (180*.72 seconds long)
design1 <- make_HRFs(onsets1, TR, duration)$design
design2 <- make_HRFs(onsets2, TR, duration)$design
x <- list(
 sessionOne = list(BOLD=BOLD1, design=design1),
 sessionTwo = list(BOLD=BOLD2, design=design2)
)
stopifnot(is.BfMRI.sess(x))