dtiIndices-methods: Methods for Function 'dtiIndices' in Package 'dti'

Description Usage Arguments Value Methods Author(s) References See Also Examples


The method creates estimates of the fractional anisotropy (FA) and relative anisotropy (RA) indices, the main directions of anisotropy and several statistics used for visualization.


  ## S4 method for signature 'dtiTensor'
dtiIndices(object, mc.cores = setCores(,reprt=FALSE))



Object of class "dtiTensor"


Number of cores to use. Defaults to number of threads specified for openMP, see documentation of package awsMethods. Our experience suggests to use 4-6 cores if available.


An object of class "dtiIndices".


obj = "ANY"

Returns a warning.

obj = "dtiTensor"

Estimate tensor indices like trace, fractional and geodesic anisotropy, main diffusion direction and shape parameters.


Karsten Tabelow [email protected]
J\"org Polzehl [email protected]


J. Polzehl and K. Tabelow, Beyond the diffusion tensor model: The package dti, Journal of Statistical Software, to appear.

K. Tabelow, H.U. Voss and J. Polzehl, Modeling the orientation distribution function by mixtures of angular central Gaussian distributions, Journal of Neuroscience Methods, to appear.

J. Polzehl and K. Tabelow, Structural adaptive smoothing in diffusion tensor imaging: The R package dti, Journal of Statistical Software, 31 (2009) pp. 1–24.

K. Tabelow, J. Polzehl, V. Spokoiny and H.U. Voss. Diffusion Tensor Imaging: Structural adaptive smoothing, NeuroImage 39(4), 1763-1773 (2008).


See Also

medinria, dtiTensor-methods, dtiTensor, dtiIndices


  ## Not run: demo(dti_art)

Example output

Loading required package: awsMethods

Use the function setCores() to change the number of CPU cores.

Loading required package: adimpro
sh: 1: cannot create /dev/null: Permission denied
sh: 1: cannot create /dev/null: Permission denied
sh: 1: cannot create /dev/null: Permission denied
Reading RAW images requires to install dcraw, see 

    http://cybercom.net/~dcoffin/dcraw/ for LINUX and http://www.insflug.org/raw/ 
    for MAC OS and Windows 

Loading required package: rgl
Warning messages:
1: In fun(libname, pkgname) : could not determine path to Imagemagick 

    please set the correct path manually using 

2: In rgl.init(initValue, onlyNULL) : RGL: unable to open X11 display
3: 'rgl_init' failed, running with rgl.useNULL = TRUE 
4: .onUnload failed in unloadNamespace() for 'rgl', details:
  call: fun(...)
  error: object 'rgl_quit' not found 

dti documentation built on May 29, 2017, 3:50 p.m.