nrrdWriter(filename​, matrix, pixelspacing, origin, encoding)

This function writes imagery and metadata to .nrrd or .nhdr medical imaging format files.

This is a complement of the function nrrdread, "NRRD Format File Reader by Jeff Mather". It does exactly the opposite: it's a NRRD files writer.
- With filename it's possible to set the path, the filename and the format (nrrd or nhdr+data). For example, a filename like '/home/mariodiaz/testfile.nhdr' will create the file at the folder /home/mariodiaz, its filename will be testfile, and it will create the header (.nhdr) appart from the data (.raw, gzip,... depending on the encoding).
- matrix is the data to put into the file. It will also set some fields at the header like dimension, space dimensions, size, type, etc.
- Pixel spacing is equivalent to the output file voxel width and should be defined as [psx, psy, psz]
- Origin should be set to [0,0,0] by default (otherwise coordinates will be shifted)
- Encoding sets data encoding. 'raw', 'ascii' or 'gzip' available.