write.dti.bval

Writes the diffusion weighting of each volume of a diffusion
MRI dataset to a plain text file, which is the bvals part of the FSL
bvecs/bvals format.

Provides functions to read and write neuroimaging data in various file formats, with a focus on 'FreeSurfer' formats. This includes, but is not limited to, the following file formats: 1) MGH/MGZ/NIFTI format files, which can contain multi-dimensional images or other data. Typically they contain time-series of three-dimensional brain scans acquired by magnetic resonance imaging (MRI). They can also contain vertex-wise measures of surface morphometry data. The MGH format is named after the Massachusetts General Hospital, and the MGZ format is a compressed version of the same format. 2) 'FreeSurfer' morphometry data files in binary 'curv' format. These contain vertex-wise surface measures, i.e., one scalar value for each vertex of a brain surface mesh. These are typically values like the cortical thickness or brain surface area at each vertex. 3) Annotation file format. This contains a brain surface parcellation derived from a cortical atlas. 4) Surface file format. Contains a brain surface mesh, given by a list of vertices and a list of faces.

Tim Schc3<a4>fer

freesurferformats

Read and Write 'FreeSurfer' Neuroimaging File Formats

Tim Schäfer

Van Essen Lab 

Montreal Neurological Institute (MNI) 

write.dti.bval function

<dl><dt>filepath</dt>
<dd>character string, path to the output file. The conventional
extension is <code>.bval</code> or <code>.bvals</code>, but that is not enforced. Files ending in
<code>.gz</code> are gzip-compressed.</dd>
<dt>bval</dt>
<dd>numeric vector, the b-value of each volume, in s/mm^2.</dd>
<dt>layout</dt>
<dd>character string, one of 'components' or 'volumes'.
<code>components</code> (the default) writes all values into a single line, which is
what the FSL tools produce, while <code>volumes</code> writes one value per line,
which is what the Human Connectome Project distributes.</dd></dl>

Arguments

Write b-values to a FSL-style bvals file. — write.dti.bval

<dl>

<dt>filepath</dt>
<dd>character string, path to the output file. The conventional
extension is <code>.bval</code> or <code>.bvals</code>, but that is not enforced. Files ending in
<code>.gz</code> are gzip-compressed.</dd>


<dt>bval</dt>
<dd>numeric vector, the b-value of each volume, in s/mm^2.</dd>


<dt>layout</dt>
<dd>character string, one of 'components' or 'volumes'.
<code>components</code> (the default) writes all values into a single line, which is
what the FSL tools produce, while <code>volumes</code> writes one value per line,
which is what the Human Connectome Project distributes.</dd>

</dl>

write.dti.bval: Write b-values to a FSL-style bvals file.

Description

Usage

Value

Arguments

See Also