Difference between revisions of "Fdkup.m"
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Returns a finite difference representation of the Kuprov operator: | Returns a finite difference representation of the Kuprov operator: | ||
K[rho]=-(1/3)*Trace(Hessian[rho]*chi) | K[rho]=-(1/3)*Trace(Hessian[rho]*chi) | ||
| − | with the number of stencil points in the finite difference approximation specified by user. | + | with the number of stencil points in the finite difference approximation specified by user. The resulting operator is a sparse matrix designed to act on the vectorisation of rho. The dimensions of rho are assumed to be ordered as [X Y Z]. For further information, see http://dx.doi.org/10.1039/C4CP03106G. |
| − | + | ==Syntax== | |
| + | |||
| + | K=fdkup(npoints,extents,chi,nstenc) | ||
| + | |||
| + | ==Arguments== | ||
| − | |||
| − | |||
npoints - a three-element vector specifying the dimensions | npoints - a three-element vector specifying the dimensions | ||
of the 3D cube of data that the operator will be | of the 3D cube of data that the operator will be | ||
| − | acting on, in Angstroms. | + | acting on, in Angstroms. The dimensions are assu- |
| + | med to be ordered as [X Y Z]. | ||
| + | |||
| + | chi - the electron magnetic susceptibility tensor in | ||
| + | cubic Angstroms, a symmatric 3x3 matrix. | ||
| + | |||
| + | extents - a three-element vector specifying axis extents | ||
| + | in Angstroms. The dimensions are assumed to be | ||
| + | ordered as [X Y Z]. | ||
| + | |||
| + | nstenc - number of finite-difference stencil points for | ||
| + | the finite-difference approximation. Periodic | ||
| + | boundary conditions are used. | ||
| − | + | ==Outputs== | |
| − | |||
| − | + | K - a sparse matrix designed to act on the vectori- | |
| − | + | zation of the array. The dimensions are assumed | |
| + | to be ordered as [X Y Z]. | ||
| − | + | ==See also== | |
| − | + | Links to related functions. | |
| − | |||
| − | + | ''Version 2.2, authors: [[Gareth Charnock]], [[Ilya Kuprov]]'' | |
Revision as of 15:28, 16 August 2018
Returns a finite difference representation of the Kuprov operator:
K[rho]=-(1/3)*Trace(Hessian[rho]*chi)
with the number of stencil points in the finite difference approximation specified by user. The resulting operator is a sparse matrix designed to act on the vectorisation of rho. The dimensions of rho are assumed to be ordered as [X Y Z]. For further information, see http://dx.doi.org/10.1039/C4CP03106G.
Contents
Syntax
K=fdkup(npoints,extents,chi,nstenc)
Arguments
npoints - a three-element vector specifying the dimensions
of the 3D cube of data that the operator will be
acting on, in Angstroms. The dimensions are assu-
med to be ordered as [X Y Z].
chi - the electron magnetic susceptibility tensor in
cubic Angstroms, a symmatric 3x3 matrix.
extents - a three-element vector specifying axis extents
in Angstroms. The dimensions are assumed to be
ordered as [X Y Z].
nstenc - number of finite-difference stencil points for
the finite-difference approximation. Periodic
boundary conditions are used.
Outputs
K - a sparse matrix designed to act on the vectori-
zation of the array. The dimensions are assumed
to be ordered as [X Y Z].
See also
Links to related functions.
Version 2.2, authors: Gareth Charnock, Ilya Kuprov
