fast from FSLfast(file, outfile = NULL, retimg = TRUE, reorient = FALSE,
intern = FALSE, opts = "", out_type = c("seg", "mixeltype", "pve_0",
"pve_1", "pve_2", "pveseg"), verbose = TRUE, ...)readNIfTI.systemfastpaste0(outfile, "_", out_type)readNIfTI.retimg then object of class nifti. Otherwise,
Result from system command, depends if intern is TRUE or FALSE.