dtiIndices-class {dti}R Documentation

Class "dtiIndices"

Description

Fractional Anisotropy indices and main directions of anisotropy derived from a diffusion tensor

Objects from the Class

Objects can be created by calls of function dtiIndices.

Slots

.Data:
Object of class "list" usually empty
fa:
Object of class "array" Fractional anisotropy values (FA)
md:
Object of class "array" Mean diffusivity values (MD)
andir:
Object of class "array" Main directions of anisotropy
bary:
Object of class "array" barycentric coordinates
btb:
Object of class "matrix" matrix of dimension c(6,ngrad) obtained from gradient directions.
ngrad:
Object of class "integer" number of gradients (including zero gradients)
s0ind:
Object of class "integer" index of zero gradients within sequence 1:ngrad
replind:
Object of class "integer" index (identifier) of unique gradient directions. Used to charactreize replications in the gradient design by identical indices. length is ngrad
level:
Object of class "numeric" minimal valid s0-level. No evaluation was be performed for voxel with s0-values less than level. Used to determine mask.
ddim:
Object of class "integer" dimension of original image cubes. Integer vector of length 3.
ddim0:
Object of class "integer" dimension of subcube defined by xind, yind and zind.
xind:
Object of class "integer" index for subcube definition in x-direction
yind:
Object of class "integer" index for subcube definition in y-direction
zind:
Object of class "integer" index for subcube definition in z-direction
voxelext:
Object of class "numeric" voxel extensions in x-, y- and z-direction. vector of length 3.
method:
Object of class "character" either "linear" or "nonlinear" or "unknown". Indicates the regression model used for estimating the tensors.
source:
Object of class "character" name of the imgfile used to create the data.

Extends

Class "list", from data part. Class "dti", directly. Class "vector", by class "list", distance 2.

Methods

plot
signature(x = "dtiIndices"): 2D Visualization for a specified slice.

Author(s)

Karsten Tabelow tabelow@wias-berlin.de, J"org Polzehl polzehl@wias-berlin.de

References

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

http://www.wias-berlin.de/projects/matheon_a3/

See Also

dtiData,dtiTensor,dti.smooth, dti, dtiData, dtiTensor

Examples

showClass("dtiIndices")
## Not run: demo(dti_art)

[Package dti version 0.5-4 Index]