matlab_class/sample_processing/example_interp.m

function []=example_interp();
% EXAMPLE_INTERP illustrates interpolation capabilities
%   by going back and forth between gcmfaces grid and
%   longitude-latitude arrays

gcmfaces_global;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
if myenv.verbose>0;
    gcmfaces_msg('===============================================');
    gcmfaces_msg(['*** entering example_interp: illustrate ' ...
        'interpolation capabilities to get in and out of gcmfaces'],'');
end;

%%%%%%%%%%%%%%%%%
%load grid and setup test case:
%%%%%%%%%%%%%%%%%

if isempty(mygrid);
   grid_load;
end;

%target locations:
lon=[-179.75:0.5:179.75]; lat=[-89.75:0.5:89.75];
[lat,lon] = meshgrid(lat,lon);

%original field:
m=mygrid.mskC(:,:,1);
fld=m.*mygrid.Depth;

%%%%%%%%%%%%%%%%%%%%%%%
%interpolate mygrid.Depth to lon-lat grid:

if myenv.verbose>0;
    gcmfaces_msg('* interpolate mygrid.Depth to lon-lat grid');
end;

fld_interp=gcmfaces_interp_2d(fld,lon,lat);

%%%%%%%%%%%%%%%%%%%%%%%
%interpolate back to mygrid.XC, mygrid.YC:

if myenv.verbose>0;
    gcmfaces_msg('* interpolate back to gcmfaces grid');
end;

fld_reinterp=gcmfaces_interp_2d(fld_interp,lon,lat,'linear');

%%%%%%%%%%%%%%%%%%%%%%%
%remap to gcmfaces grid using extrapolation:

if myenv.verbose>0;
    gcmfaces_msg('* remap to gcmfaces grid using extrapolation');
end;

fld_remap=gcmfaces_remap_2d(lon,lat,fld_interp,0,m);

%%%%%%%%%%%%%%%%%%%%%%%
%illustrate results:

figureL;
subplot(2,1,1); set(gca,'FontSize',14);
[X,Y,FLD]=convert2pcol(mygrid.XC,mygrid.YC,fld);
pcolor(X,Y,FLD); axis([-180 180 -90 90]); shading flat;
title('original field');
subplot(2,1,2); set(gca,'FontSize',14);
pcolor(lon,lat,fld_interp); axis([-180 180 -90 90]); shading flat;
title('interpolated field');

figureL;
subplot(2,1,1); set(gca,'FontSize',14);
[X,Y,FLD]=convert2pcol(mygrid.XC,mygrid.YC,fld_reinterp);
pcolor(X,Y,FLD); axis([-180 180 -90 90]); shading flat;
title('reinterpolated field');
subplot(2,1,2); set(gca,'FontSize',14);
[X,Y,FLD]=convert2pcol(mygrid.XC,mygrid.YC,fld_remap);
pcolor(X,Y,FLD); axis([-180 180 -90 90]); shading flat;
title('remapped field');


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
if myenv.verbose>0;
    gcmfaces_msg('*** leaving example_interp');
    gcmfaces_msg('===============================================');
end;


1	gforget	1.13	function []=example_interp();
2	gforget	1.16	% EXAMPLE_INTERP illustrates interpolation capabilities
3			% by going back and forth between gcmfaces grid and
4			% longitude-latitude arrays
5
6			gcmfaces_global;
7
8			%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
9			if myenv.verbose>0;
10			gcmfaces_msg('===============================================');
11			gcmfaces_msg(['*** entering example_interp: illustrate ' ...
12			'interpolation capabilities to get in and out of gcmfaces'],'');
13			end;
14	gforget	1.1
15			%%%%%%%%%%%%%%%%%
16	gforget	1.16	%load grid and setup test case:
17	gforget	1.1	%%%%%%%%%%%%%%%%%
18
19	gforget	1.15	if isempty(mygrid);
20			grid_load;
21			end;
22	gforget	1.12
23	gforget	1.16	%target locations:
24			lon=[-179.75:0.5:179.75]; lat=[-89.75:0.5:89.75];
25			[lat,lon] = meshgrid(lat,lon);
26
27			%original field:
28			m=mygrid.mskC(:,:,1);
29			fld=m.*mygrid.Depth;
30	gforget	1.1
31			%%%%%%%%%%%%%%%%%%%%%%%
32	gforget	1.16	%interpolate mygrid.Depth to lon-lat grid:
33
34	gforget	1.12	if myenv.verbose>0;
35	gforget	1.16	gcmfaces_msg('* interpolate mygrid.Depth to lon-lat grid');
36	gforget	1.12	end;
37	gforget	1.16
38			fld_interp=gcmfaces_interp_2d(fld,lon,lat);
39	gforget	1.1
40			%%%%%%%%%%%%%%%%%%%%%%%
41	gforget	1.17	%interpolate back to mygrid.XC, mygrid.YC:
42	gforget	1.1
43	gforget	1.16	if myenv.verbose>0;
44	gforget	1.17	gcmfaces_msg('* interpolate back to gcmfaces grid');
45			end;
46
47	gforget	1.18	fld_reinterp=gcmfaces_interp_2d(fld_interp,lon,lat,'linear');
48	gforget	1.17
49			%%%%%%%%%%%%%%%%%%%%%%%
50			%remap to gcmfaces grid using extrapolation:
51
52			if myenv.verbose>0;
53			gcmfaces_msg('* remap to gcmfaces grid using extrapolation');
54	gforget	1.1	end;
55
56	gforget	1.16	fld_remap=gcmfaces_remap_2d(lon,lat,fld_interp,0,m);
57
58	gforget	1.1	%%%%%%%%%%%%%%%%%%%%%%%
59	gforget	1.16	%illustrate results:
60	gforget	1.1
61	gforget	1.12	figureL;
62	gforget	1.17	subplot(2,1,1); set(gca,'FontSize',14);
63	gforget	1.16	[X,Y,FLD]=convert2pcol(mygrid.XC,mygrid.YC,fld);
64			pcolor(X,Y,FLD); axis([-180 180 -90 90]); shading flat;
65			title('original field');
66	gforget	1.17	subplot(2,1,2); set(gca,'FontSize',14);
67	gforget	1.16	pcolor(lon,lat,fld_interp); axis([-180 180 -90 90]); shading flat;
68			title('interpolated field');
69	gforget	1.17
70			figureL;
71			subplot(2,1,1); set(gca,'FontSize',14);
72			[X,Y,FLD]=convert2pcol(mygrid.XC,mygrid.YC,fld_reinterp);
73			pcolor(X,Y,FLD); axis([-180 180 -90 90]); shading flat;
74			title('reinterpolated field');
75			subplot(2,1,2); set(gca,'FontSize',14);
76	gforget	1.16	[X,Y,FLD]=convert2pcol(mygrid.XC,mygrid.YC,fld_remap);
77	gforget	1.12	pcolor(X,Y,FLD); axis([-180 180 -90 90]); shading flat;
78	gforget	1.16	title('remapped field');
79
80
81			%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
82			if myenv.verbose>0;
83			gcmfaces_msg('*** leaving example_interp');
84			gcmfaces_msg('===============================================');
85			end;
86	gforget	1.1
87