A method of S2BumpKernel.

the derivative of the bump kernel, zero wherever it exists

Syntax

d = psi.grad(t)

Zero at every cosine t.

d = psi.grad(v, zvector)

Zero at every direction v.

dpsi = psi.grad()

The zero kernel.

Description

The bump kernel is constant on its cap and beyond it, so its derivative vanishes but on the rim of the cap, where it does not exist; the derivative in the angle and in its cosine agree.

Input

psi S2BumpKernel
t ndarray of cosines, or vector3d
other vector3d, the direction the angles of t are measured from

Keywords

keyword default description
polynomial False the derivative with respect to the cosine, the same zero

Output

d ndarray of zeros, or the zero S2Kernel without an argument

See also

S2Kernel.grad, S2BumpKernel

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/S2BumpKernel.grad_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.