y = gaussnd(p, x, y, ..., signal) : nD Gaussian
iFunc/gaussnd nD Gaussian fitting function
y = R0 * exp(-[x,y,...]' * G * [x,y,...])
a multi-dimensional Gaussian profile
<http://en.wikipedia.org/wiki/Gaussian_function#Multi-dimensional_Gaussian_function>
This model has no background, is centered, and has maximum intensity set to 1.
The parameters correspond to widths.
MODEL CREATION
gaussnd([w1 w2 ... wn ])
builds a 'n' Dimensional orthogonal Gaussian with widths [w1 w2 ...]
gaussnd(M)
where M is a square matrix [n x n] builds a 'n' Dimensional.
if M is non symmetric, it is made so from (M+M')/2
gaussnd('ResLibCal') extracts a 4D TAS resolution function from ResLibCal
gaussnd('defaults')
builds a 2D Gaussian
gaussnd and gaussnd('gui')
shows a Dialogue to enter the Gaussian matrix, widths or other option.
MODEL EVALUATION
input: p: Gaussian model matrix (double, symmetric ndims*ndims)
p = [ ndims(G) * ndims(G) values ]
or 'guess'
x,y,...: axes (double)
signal: when values are given and p='guess', a guess of the parameters is performed (double)
output: y: model value
ex: y=gaussnd([1 0 1 1], -10:10, -10:10); or plot(gaussnd)
Version: Nov. 26, 2018
See also iFunc, iFunc/fits, iFunc/plot, gauss2d, gauss
(c) E.Farhi, ILL. License: EUPL.