Load transformation matrix from a file.
read.fs.transform(filepath, format = "auto")| filepath | character string, the full path to the transform file. |
|---|---|
| format | character string, the file format. Currently 'auto' (guess based on file extension), 'xfm' (for xform format) or 'dat' (for tkregister style, e.g. register.dat) are supported. |
named list, the 'matrix field contains a '4x4 numerical matrix, the transformation matrix. Other fields may exist, depending on the parsed format.
Currently this function has been tested with linear transformation files only, all others are unsupported.
Other header coordinate space:
mghheader.is.ras.valid(),
mghheader.ras2vox.tkreg(),
mghheader.ras2vox(),
mghheader.scanner2tkreg(),
mghheader.tkreg2scanner(),
mghheader.vox2ras.tkreg(),
mghheader.vox2ras(),
read.fs.transform.dat(),
read.fs.transform.lta(),
read.fs.transform.xfm(),
sm0to1(),
sm1to0()
tf_file = system.file("extdata", "talairach.xfm",
package = "freesurferformats",
mustWork = TRUE);
transform = read.fs.transform(tf_file);
transform$matrix;
#> [,1] [,2] [,3] [,4]
#> [1,] 1.111536 0.040948 0.012535 -0.803558
#> [2,] -0.029730 0.981154 0.342306 -19.558083
#> [3,] 0.022961 -0.452588 1.111222 10.044540
#> [4,] 0.000000 0.000000 0.000000 1.000000