A method of S2FunBingham.

the Bingham distribution fitted to directions or axes, with the confidence ellipse of its modal axis

Syntax

f = S2FunBingham.fit(v)

The fitted distribution.

f = S2FunBingham.fit(v, weights=w)

Weighted directions.

f, ab, rot = S2FunBingham.fit(v, confidenceEllipse=True, p=0.95)

With the confidence ellipse.

Description

The eigen decomposition of the scatter matrix of the directions, sum of w v v^T, gives the axes of the distribution, and Newton’s method on the moments its shape parameters, ascending to zero at the third axis, the mode. A direction and its antipode count alike.

The confidence ellipse of the modal axis is the asymptotic covariance of the largest eigenvector, Tanaka’s: its semi-axes ab in radians and the rotation rot turning the z axis onto the mode, drawn by ellipse(rot, ab[0], ab[1]).

Input

v vector3d or Miller, the directions or axes

Keywords

keyword default description
weights None the weights of the directions, equal by default
confidenceEllipse False return also ab and rot, MATLAB’s second and third output
p 0.95 the confidence level of the ellipse

Output

f S2FunBingham, in the frame of v
ab the two semi-axes of the confidence ellipse in radians
rot rotation, the position of the confidence ellipse

References

  • H. Tanaka, Circular asymmetry of the paleomagnetic directions observed at low latitude volcanic sites, Earth Planets Space 51 (1999) 1279-1286

See also

S2FunBingham, BinghamODF, calcBinghamODF, ellipse

MATLAB’s S2FunBingham.fit

source

Citing this page. This page is part of the documentation of MTEX, a free and open source MATLAB toolbox for analyzing and modeling crystallographic textures. It was written by The MTEX Developers and is published at https://mtex-toolbox.github.io/S2FunBingham.fit_py.html. If you use MTEX, or reuse text or figures from this page, in your research, please cite

F. Bachmann, R. Hielscher, H. Schaeben: Texture Analysis with MTEX - Free and Open Source Software Toolbox, Solid State Phenomena 160 (2010), 63-68. 10.4028/www.scientific.net/SSP.160.63

BibTeX
@article{bachmann2010mtex,
  author  = {F. Bachmann and R. Hielscher and H. Schaeben},
  title   = {Texture Analysis with MTEX - Free and Open Source Software Toolbox},
  journal = {Solid State Phenomena},
  volume  = {160},
  pages   = {63-68},
  year    = {2010},
  doi     = {10.4028/www.scientific.net/SSP.160.63},
  url     = {https://doi.org/10.4028/www.scientific.net/SSP.160.63}
}

Other papers describing specific MTEX methods are listed under Publications — please cite the one that best fits your application. The MTEX source code is licensed under the GNU General Public License v2.0; the text and figures of this documentation are licensed under CC BY 4.0, which permits reuse — including by automated systems — provided The MTEX Developers and this page are credited.