Changeset 247 for trunk/src/tps_eval_dxy.m

Timestamp:

Apr 29, 2011, 6:44:35 PM (13 years ago)

Author:

sommeria

Message:

thin plate shell corrected for spatial derivatives

File:

• trunk/src/tps_eval_dxy.m (modified) (2 diffs)

trunk/src/tps_eval_dxy.m

@@ -11 +11 @@
 %            N centres, with s=space dimension, DMXY(:,:,k) gives the derivatives
 %            along dimension k (=x, y,z) after multiplication by the N+1+s tps sources.
-  function DMXY = tps_eval_dxy(dsites,ctrs)
+  function [DMX,DMY] = tps_eval_dxy(dsites,ctrs)
   %%  matrix declarations
   [M,s] = size(dsites); [N,s] = size(ctrs);
-  Dsites=zeros(M,N,s);
+  Dsites=zeros(M,N);
   DM = zeros(M,N);
-  DMXY = zeros(M,N+1+s,s);
+ % DMXY = zeros(M,N+1+s);
   
   %% Accumulate sum of squares of coordinate differences
@@ -24 +24 @@
   %  Ctrs, consisting of M identical rows (each containing
   %       the d-th coordinate of the N centers)
-  for d=1:s
-     [Dsites(:,:,d),Ctrs] = ndgrid(dsites(:,d),ctrs(:,d));%d coordinates of interpolation points (Dsites) and initial points (Ctrs)
-     DM = DM + (Dsites(:,:,d)-Ctrs).^2;% add d component squared 
-  end
   
-  %% calculate mtrix of tps derivatives
-  DM(DM~=0) = log(DM)+1; %=2 log(r)+1 derivative of the tps r^2 log(r)
-  for d=1:s
-    DMXY(:,1:N,d)=Dsites(:,:,d).*DM;
-    DMXY(:,N+1+d,d)=1;% effect of mean gradient
-  end
+[Dsites,Ctrs] = ndgrid(dsites(:,1),ctrs(:,1));%d coordinates of interpolation points (Dsites) and initial points (Ctrs)
+DX=Dsites-Ctrs;
+[Dsites,Ctrs] = ndgrid(dsites(:,2),ctrs(:,2));%d coordinates of interpolation points (Dsites) and initial points (Ctrs)
+DY=Dsites-Ctrs;
+DM = DX.*DX + DY.*DY;% add d component squared 
+
+ %% calculate matrix of tps derivatives
+DM(DM~=0) = log(DM(DM~=0))+1; %=2 log(r)+1 derivative of the tps r^2 log(r)
+
+DMX=[DX.*DM zeros(M,1)  ones(M,1) zeros(M,1)];% effect of mean gradient
+DMY=[DY.*DM zeros(M,1)  ones(M,1) zeros(M,1)];% effect of mean gradient
+