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gforget |
1.5 |
function []=example_faces2latlon2faces(); |
| 2 |
gforget |
1.1 |
%object: interpolate back and forth between gcmfaces and lat-lon grid |
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gforget |
1.6 |
%%%%%%%%%%%%%%%%% |
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%load grid: |
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%%%%%%%%%%%%%%%%% |
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p = genpath('gcmfaces/'); addpath(p); |
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p = genpath('MITprof/'); addpath(p); |
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gcmfaces_global; |
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mygrid=[]; grid_load; |
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gforget |
1.1 |
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if myenv.verbose>0; |
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gcmfaces_msg('==============================================='); |
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gcmfaces_msg(['*** entering example_faces2latlon2faces that will ' ... |
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'interpolate a field on the chosen to a lat-lon grid and back' ... |
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'to the original grid'],''); |
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end; |
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%store reference grid |
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mygrid_refgrid=mygrid; |
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gforget |
1.6 |
%triangulation variable generated by gcmfaces_bindata |
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global mytri; |
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gforget |
1.1 |
%%%%%%%%%%%%%%%%%%% |
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%field for testing: |
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%%%%%%%%%%%%%%%%%%% |
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if myenv.verbose>0; |
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gcmfaces_msg('* define a sinusoidal field for testing'); |
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end; |
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fld=sin(2*pi/180*mygrid.XC).*sin(2*pi/180*mygrid.YC); |
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%%%%%%%%%%%%%%%%%%%%%%%%%% |
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%lat-lon grid for testing: |
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%%%%%%%%%%%%%%%%%%%%%%%%%% |
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if myenv.verbose>0; |
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gcmfaces_msg('* define 2x2 lat-lon grid for testing'); |
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end; |
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%define lat-lon grid |
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lon=[-179:2:179]; lat=[-89:2:89]; aa=[-180 180 -90 90]; |
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if max(mygrid_refgrid.XC)>180; |
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lon=[1:2:359]; aa=[0 360 -90 90]; |
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end; |
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% lon=[-179:2:179]; lat=[-30:2:30]; |
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[lat,lon] = meshgrid(lat,lon); |
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%prepare mygrid for lat-lon with no mask |
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mygrid_latlon.nFaces=1; |
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mygrid_latlon.XC=gcmfaces({lon}); mygrid_latlon.YC=gcmfaces({lat}); |
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gforget |
1.3 |
mygrid_latlon.dirGrid='none'; |
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mygrid_latlon.fileFormat='straight'; |
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mygrid_latlon.ioSize=size(lon); |
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gforget |
1.1 |
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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%interpolate to lat-lon grid: |
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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if myenv.verbose>0; |
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gcmfaces_msg('* interpolate test field to lat-lon grid'); |
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end; |
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mygrid=mygrid_latlon; gcmfaces_bindata; |
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veclon=convert2array(mygrid.XC); veclon=veclon(mytri.kk); |
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veclat=convert2array(mygrid.YC); veclat=veclat(mytri.kk); |
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mygrid=mygrid_refgrid; gcmfaces_bindata; |
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vecfld=gcmfaces_interp_2d(fld,veclon,veclat);%go from gcmfaces grid to lat-lon grid |
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mygrid=mygrid_latlon; gcmfaces_bindata; |
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fld_latlon=NaN*convert2array(mygrid.XC); |
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fld_latlon(mytri.kk)=vecfld; |
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fld_latlon=convert2array(fld_latlon); |
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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%interpolate back to ref grid: |
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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if myenv.verbose>0; |
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gcmfaces_msg('* interpolate back to original grid'); |
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end; |
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mygrid=mygrid_refgrid; gcmfaces_bindata; |
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veclon=convert2array(mygrid.XC); veclon=veclon(mytri.kk); |
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veclat=convert2array(mygrid.YC); veclat=veclat(mytri.kk); |
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mygrid=mygrid_latlon; gcmfaces_bindata; |
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vecfld=gcmfaces_interp_2d(fld_latlon,veclon,veclat);%go from gcmfaces grid to lat-lon grid |
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mygrid=mygrid_refgrid; gcmfaces_bindata; |
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fld_refgrid=NaN*convert2array(mygrid.XC); |
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fld_refgrid(mytri.kk)=vecfld; |
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fld_refgrid=convert2array(fld_refgrid); |
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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%get and plot the lat-lon array: |
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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if myenv.verbose>0; |
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gcmfaces_msg('* plot lat-lon grid interpolated field'); |
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end; |
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FLD=fld_latlon{1}; |
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gforget |
1.4 |
figureL; |
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subplot(2,1,1); set(gca,'FontSize',14); |
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pcolor(lon,lat,FLD); axis([-270 270 -100 100]); |
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shading flat; colorbar; title('interpolated lat-lon map'); |
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gforget |
1.1 |
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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%plot difference due to interpolation |
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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if myenv.verbose>0; |
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gcmfaces_msg('* plot error due to back and forth interpolation'); |
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end; |
| 116 |
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mygrid=mygrid_refgrid; |
| 117 |
gforget |
1.4 |
subplot(2,1,2); set(gca,'FontSize',14); |
| 118 |
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[X,Y,FLD]=convert2pcol(mygrid.XC,mygrid.YC,fld_refgrid-fld); |
| 119 |
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pcolor(X,Y,log10(abs(FLD))); axis([-270 270 -100 100]); |
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shading flat; caxis([-5 -2]); colorbar; |
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title('log10(error) due to back and forth interpolation'); |
| 122 |
gforget |
1.1 |
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if myenv.verbose>0; |
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gcmfaces_msg('*** leaving example_faces2latlon2faces'); |
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gcmfaces_msg('==============================================='); |
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end; |
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