/[MITgcm]/MITgcm_contrib/gael/matlab_class/gcmfaces_misc/gcmfaces_interp_coeffs.m
ViewVC logotype

Annotation of /MITgcm_contrib/gael/matlab_class/gcmfaces_misc/gcmfaces_interp_coeffs.m

Parent Directory Parent Directory | Revision Log Revision Log | View Revision Graph Revision Graph


Revision 1.6 - (hide annotations) (download)
Mon Feb 1 14:32:23 2016 UTC (9 years, 5 months ago) by gforget
Branch: MAIN
CVS Tags: checkpoint65t
Changes since 1.5: +12 -1 lines
- add prof_interp.XC, prof_interp.YC output

1 gforget 1.2 function [prof_interp,tile_corners]=gcmfaces_interp_coeffs(prof_lon,prof_lat,varargin);
2 gforget 1.1 %[prof_interp]=gcmfaces_interp_coeffs(prof_lon,prof_lat);
3     %object: compute bilinear interpolation weights for prof_lon, prof_lat
4     %inputs: prof_lon, prof_lat are column vectors
5     %(optional) ni,nj is the MITgcm tile size (2 numbers total)
6     %outputs: prof_interp contains face and tile numbers,
7     % indices within tiles (within 0:ni+1,0:nj+1)
8     % and interpolation weights (between 0 and 1)
9     % of the four neighboring grid points.
10 gforget 1.2 %(optional) tile_corners contains XC11,XCNINJ,YC11,YCNINJ (for MITprof)
11 gforget 1.1 %
12     %note: pathological cases (e.g. at edges) remain to be treated.
13     %example:
14     %prof=MITprof_load('ctd_feb2013.nc');
15     %[prof_interp]=gcmfaces_interp_coeffs(prof.prof_lon,prof.prof_lat);
16    
17     gcmfaces_global;
18    
19     doDisplay=0;
20 gforget 1.4 doVerbose=0; if myenv.verbose>=1; doVerbose=myenv.verbose; end;
21 gforget 1.5 %set doVerbose to display points that could not be triangulated (if any)
22 gforget 1.1
23     %set-up tile information (domain decomposition to ni,nj blocs)
24     if nargin<=2;
25     ni=30; nj=30;
26     else;
27     ni=varargin{1};
28     nj=varargin{2};
29     end;
30    
31     map_tile=gcmfaces_loc_tile(ni,nj);
32     loc_tile=gcmfaces_loc_tile(ni,nj,prof_lon,prof_lat);
33     prof_tile=loc_tile.tileNo;
34     list_tile=unique(prof_tile);
35    
36     %initialize output:
37 gforget 1.6 prof_interp.point=loc_tile.point;
38 gforget 1.1 prof_interp.face=NaN*prof_lon;
39     prof_interp.tile=NaN*prof_lon;
40     prof_interp.i=NaN*repmat(prof_lon,[1 4]);
41     prof_interp.j=NaN*repmat(prof_lon,[1 4]);
42     prof_interp.w=NaN*repmat(prof_lon,[1 4]);
43 gforget 1.6 prof_interp.XC=NaN*repmat(prof_lon,[1 4]);
44     prof_interp.YC=NaN*repmat(prof_lon,[1 4]);
45 gforget 1.2 %
46     tile_corners.XC11=NaN*prof_lon;
47     tile_corners.YC11=NaN*prof_lon;
48     tile_corners.XCNINJ=NaN*prof_lon;
49     tile_corners.YCNINJ=NaN*prof_lon;
50 gforget 1.1
51     %loop over tiles
52     for ii=1:length(list_tile);
53     %1) determine face of current tile ...
54     tmp1=1*(map_tile==list_tile(ii));
55     tmp11=sum(sum(tmp1,1),2); tmp12=[];
56     for ff=1:tmp11.nFaces; tmp12=[tmp12,tmp11{ff}]; end;
57     iiFace=find(tmp12);
58     %... and its index range within face ...
59     tmp1=tmp1{iiFace};
60     tmp11=sum(tmp1,2);
61     iiMin=min(find(tmp11)); iiMax=max(find(tmp11));
62     tmp11=sum(tmp1,1);
63     jjMin=min(find(tmp11)); jjMax=max(find(tmp11));
64     %... as well as the list of profiles in tile
65     ii_prof=find(prof_tile==list_tile(ii));
66 gforget 1.2 %tile corners
67     XC11=mygrid.XC{iiFace}(iiMin,jjMin);
68     YC11=mygrid.YC{iiFace}(iiMin,jjMin);
69     XCNINJ=mygrid.XC{iiFace}(iiMax,jjMax);
70     YCNINJ=mygrid.YC{iiFace}(iiMax,jjMax);
71    
72 gforget 1.1 clear tmp*;
73    
74     %2) stereographic projection to current tile center:
75     ii0=floor((iiMin+iiMax)/2);
76     jj0=floor((jjMin+jjMax)/2);
77     XC0=mygrid.XC{iiFace}(ii0,jj0);
78     YC0=mygrid.YC{iiFace}(ii0,jj0);
79     %for grid locations:
80     [xx,yy]=gcmfaces_stereoproj(XC0,YC0);
81     %for profile locations
82     [prof_x,prof_y]=gcmfaces_stereoproj(XC0,YC0,prof_lon,prof_lat);
83    
84     % nrm=sqrt(prof_x.^2+prof_y.^2);
85     %ii_prof=find(nrm<tan(pi/4/2));%points inside of pi/4 cone
86    
87     %3) form array of grid cell quadrilaterals
88     xxx=exch_T_N(xx); yyy=exch_T_N(yy);
89 gforget 1.6 xc=exch_T_N(mygrid.XC); yc=exch_T_N(mygrid.YC);
90     x_quad=[]; y_quad=[]; xc_quad=[]; yc_quad=[]; i_quad=[]; j_quad=[];
91 gforget 1.1 for pp=1:4;
92     switch pp;
93     case 1; di=0; dj=0;
94     case 2; di=1; dj=0;
95     case 3; di=1; dj=1;
96     case 4; di=0; dj=1;
97     end;
98     %note the shift in indices due to exchange above
99     tmpx=xxx{iiFace}(iiMin+di:iiMax+1+di,jjMin+dj:jjMax+1+dj);
100     tmpx=tmpx(:); x_quad=[x_quad tmpx];
101     tmpy=yyy{iiFace}(iiMin+di:iiMax+1+di,jjMin+dj:jjMax+1+dj);
102     tmpy=tmpy(:); y_quad=[y_quad tmpy];
103     %
104 gforget 1.6 tmpx=xc{iiFace}(iiMin+di:iiMax+1+di,jjMin+dj:jjMax+1+dj);
105     tmpx=tmpx(:); xc_quad=[xc_quad tmpx];
106     tmpy=yc{iiFace}(iiMin+di:iiMax+1+di,jjMin+dj:jjMax+1+dj);
107     tmpy=tmpy(:); yc_quad=[yc_quad tmpy];
108     %
109 gforget 1.1 tmpi=[0+di:iiMax-iiMin+1+di]'*ones(1,jjMax-jjMin+2);
110     tmpi=tmpi(:); i_quad=[i_quad tmpi];
111     tmpj=ones(jjMax-jjMin+2,1)*[0+dj:jjMax-jjMin+1+dj];
112     tmpj=tmpj(:); j_quad=[j_quad tmpj];
113     end;
114    
115     %4) associate profile locations with quadrilaterals
116     [angsum]=gcmfaces_polygonangle(x_quad,y_quad,prof_x(ii_prof),prof_y(ii_prof));
117     [II,JJ]=find(abs(angsum)>179);%+-360 for an interior point (+-180 for an edge point)
118     if length(unique(JJ))~=length(JJ)&doVerbose;
119     n0=num2str(length(JJ)-length(unique(JJ)));
120     warning(['multiple polygons (' n0 ')']);
121 gforget 1.4 %store indices of such instances for display
122     [a,b]=hist(JJ,unique(JJ));
123     KK=find(a>1);
124     kk_prof=ii_prof(KK);
125     kk_quad={};
126     for kk=1:length(KK);
127     kk_quad{kk}=II(find(JJ==KK(kk)));
128     end
129     else;
130     kk_prof=[];
131 gforget 1.1 end;
132     if length(unique(JJ))<length(ii_prof)&doVerbose;
133     n0=num2str(length(ii_prof)-length(unique(JJ)));
134     n1=num2str(length(ii_prof));
135     warning(['no polygon for ' n0 ' / ' n1]);
136     %the following will then remove the corresponding profiles form ii_prof
137     end;
138     [C,IA,IC] = unique(JJ);
139     %
140     ii_prof0=ii_prof;
141     ii_prof=ii_prof(C);%treated profiles
142     jj_prof=setdiff(ii_prof0,ii_prof);%un-treated profiles
143     %
144     ii_quad=II(IA);
145 gforget 1.4
146     if length(kk_prof)>0&doVerbose>=3;
147     for kk=1:length(kk_prof);
148     figureL;
149     tmpx=x_quad(kk_quad{kk},[1:4 1])';
150     tmpy=y_quad(kk_quad{kk},[1:4 1])';
151     plot(tmpx,tmpy,'k.-','MarkerSize',36); hold on;
152     plot(prof_x(kk_prof(kk)),prof_y(kk_prof(kk)),'r.','MarkerSize',36)
153     aa=axis;
154     aa(1:2)=aa(1:2)+abs(diff(aa(1:2)))*[-0.1 0.1];
155     aa(3:4)=aa(3:4)+abs(diff(aa(3:4)))*[-0.1 0.1];
156     axis(aa);
157     keyboard;
158     end;
159     end;
160    
161     if length(jj_prof)>0&doVerbose>=2;
162     figureL;
163     %
164     subplot(2,1,1);
165     plot(prof_x(ii_prof),prof_y(ii_prof),'.');
166     hold on; plot(x_quad(:),y_quad(:),'r.');
167     plot(prof_x(jj_prof),prof_y(jj_prof),'k.','MarkerSize',36);
168     %
169     subplot(2,1,2);
170     tmpx=convert2vector(mygrid.XC);
171     tmpy=convert2vector(mygrid.YC);
172     tmpi=convert2vector(map_tile);
173     tmpi=find(tmpi==ii);
174     plot(tmpx(:),tmpy(:),'r.'); hold on;
175     plot(tmpx(tmpi),tmpy(tmpi),'c.');
176     plot(prof_lon(ii_prof),prof_lat(ii_prof),'.');
177     plot(prof_lon(jj_prof),prof_lat(jj_prof),'k.','MarkerSize',36);
178     %
179     tmp1=prof_lon([ii_prof;jj_prof]);
180     tmp2=prof_lat([ii_prof;jj_prof]);
181     axis([min(tmp1) max(tmp1) min(tmp2) max(tmp2)]);
182     %
183     keyboard;
184     end;
185 gforget 1.1
186     if doDisplay;
187     figureL;
188     xx_tile=xxx{iiFace}(iiMin:iiMax+2,jjMin:jjMax+2);
189     yy_tile=yyy{iiFace}(iiMin:iiMax+2,jjMin:jjMax+2);
190     pcolor(xx_tile,yy_tile,sqrt(xx_tile.^2+yy_tile.^2)); hold on;
191     cc=caxis; cc(2)=cc(2)*2; caxis(cc);
192     plot(prof_x(ii_prof),prof_y(ii_prof),'r.','MarkerSize',20);
193     plot(prof_x(jj_prof),prof_y(jj_prof),'k.','MarkerSize',60);
194     axis([-0.6 0.6 -0.6 0.6]/6);
195     end;
196    
197     if ~isempty(ii_prof);
198     %5) determine bi-linear interpolation weights:
199     px=x_quad(ii_quad,:);
200     py=y_quad(ii_quad,:);
201     ox=prof_x(ii_prof);
202     oy=prof_y(ii_prof);
203     [ow]=gcmfaces_quadmap(px,py,ox,oy);
204    
205     %to double check interpolation
206     % pw=squeeze(ow);
207     % oxInterp=sum(pw.*px,2);
208     % oyInterp=sum(pw.*py,2);
209 gforget 1.3
210     %round up coefficient to 4th digit (also to avoid slight negatives)
211     test1=~isempty(find(ow(:)<-1e-5));
212     if test1; error('interp weight < 0 -- something went wrong'); end;
213     test1=~isempty(find(ow(:)>1+1e-5));
214     if test1; error('interp weight >1 -- something went wrong'); end;
215     %
216     ow=1e-4*round(ow*1e4);
217     sumw=repmat(sum(ow,3),[1 1 4]);
218     ow=ow./sumw;
219 gforget 1.1
220     %6) output interpolation specs:
221     prof_interp.face(ii_prof,1)=iiFace*(1+0*ii_quad);
222     prof_interp.tile(ii_prof,1)=list_tile(ii)*(1+0*ii_quad);
223     prof_interp.i(ii_prof,:)=i_quad(ii_quad,:);
224     prof_interp.j(ii_prof,:)=j_quad(ii_quad,:);
225     prof_interp.w(ii_prof,:)=squeeze(ow);
226 gforget 1.6 prof_interp.XC(ii_prof,:)=xc_quad(ii_quad,:);
227     prof_interp.YC(ii_prof,:)=yc_quad(ii_quad,:);
228 gforget 1.2 %
229     tile_corners.XC11(ii_prof)=XC11;
230     tile_corners.YC11(ii_prof)=YC11;
231     tile_corners.XCNINJ(ii_prof)=XCNINJ;
232     tile_corners.YCNINJ(ii_prof)=YCNINJ;
233 gforget 1.1 end;
234    
235     end;%for ii=1:length(list_tile);
236    
237 gforget 1.5 if doVerbose;
238     n1=sum(~isnan(prof_interp.face));
239     n2=sum(isnan(prof_interp.face));
240     fprintf(['interpolated points: ' num2str(n1) '\n']);
241     fprintf(['un-treated points: ' num2str(n2) '\n']);
242     end;
243 gforget 1.1

  ViewVC Help
Powered by ViewVC 1.1.22