1 ## Copyright (C) 2006 Alexander Barth
3 ## This program is free software; you can redistribute it and/or modify
4 ## it under the terms of the GNU General Public License as published by
5 ## the Free Software Foundation; either version 2 of the License, or
6 ## (at your option) any later version.
8 ## This program is distributed in the hope that it will be useful,
9 ## but WITHOUT ANY WARRANTY; without even the implied warranty of
10 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 ## GNU General Public License for more details.
13 ## You should have received a copy of the GNU General Public License
14 ## along with this program; If not, see <http://www.gnu.org/licenses/>.
17 ## @deftypefn {Loadable Function} {[@var{fi},@var{vari}] = } optiminterp2(@var{x},@var{y},@var{f},@var{var},@var{lenx},@var{leny},@var{m},@var{xi},@var{yi})
18 ## Performs a local 2D-optimal interpolation (objective analysis).
20 ## Every elements in @var{f} corresponds to a data point (observation)
21 ## at location @var{x},@var{y} with the error variance @var{var}.
23 ## @var{lenx} and @var{leny} are correlation length in x-direction
24 ## and y-direction respectively.
25 ## @var{m} represents the number of influential points.
27 ## @var{xi} and @var{yi} are the data points where the field is
28 ## interpolated. @var{fi} is the interpolated field and @var{vari} is
29 ## its error variance.
31 ## The background field of the optimal interpolation is zero.
32 ## For a different background field, the background field
33 ## must be subtracted from the observation, the difference
34 ## is mapped by OI onto the background grid and finally the
35 ## background is added back to the interpolated field.
36 ## The error variance of the background field is assumed to
37 ## have a error variance of one.
40 ## Copyright (C) 2006, Alexander Barth
41 ## Author: Alexander Barth <barth.alexander@gmail.com>
43 function [fi,vari] = optiminterp2(x,y,f,var,lenx,leny,m,xi,yi)
45 [fi,vari] = optiminterpn(x,y,f,var,lenx,leny,m,xi,yi);