SurfStatInd2Coord

Converts a vertex index to x,y,z coordinates.

 Usage: coord = SurfStatInd2Coord( ind, surf );

 ind          = 1 x c vector of indices of vertex, 1-based.
 surf.coord   = 3 x v matrix of coordinates.
 or
 surf.lat     = 3D logical array, 1=in, 0=out. 
 surf.vox     = 1 x 3 vector of voxel sizes in mm, [1 1 1] by default.
 surf.origin  = position in mm of the first voxel, [0 0 0] by default.

 coord = 3 x c matrix of coordinates.

0001 function coord = SurfStatInd2Coord( ind, surf );
0002 
0003 %Converts a vertex index to x,y,z coordinates.
0004 %
0005 % Usage: coord = SurfStatInd2Coord( ind, surf );
0006 %
0007 % ind          = 1 x c vector of indices of vertex, 1-based.
0008 % surf.coord   = 3 x v matrix of coordinates.
0009 % or
0010 % surf.lat     = 3D logical array, 1=in, 0=out.
0011 % surf.vox     = 1 x 3 vector of voxel sizes in mm, [1 1 1] by default.
0012 % surf.origin  = position in mm of the first voxel, [0 0 0] by default.
0013 %
0014 % coord = 3 x c matrix of coordinates.
0015 
0016 if isfield(surf,'coord')
0017     coord=surf.coord(:,ind);
0018 end
0019 if isfield(surf,'lat')
0020     if ~isfield(surf,'vox')
0021         surf.vox=ones(1,3);
0022     end
0023     if ~isfield(surf,'origin');
0024         surf.origin=zeros(1,3);
0025     end
0026     vid=cumsum(surf.lat(:)).*surf.lat(:);
0027     [tf,loc]=ismember(ind,vid);
0028     loc(loc==0)=NaN;
0029     dim=size(surf.lat);
0030     [i,j,k]=ind2sub(dim,loc);
0031     coord=zeros(3,length(ind));
0032     coord(1,:)=surf.origin(1)+(i-1)*surf.vox(1);
0033     coord(2,:)=surf.origin(2)+(j-1)*surf.vox(2);
0034     coord(3,:)=surf.origin(3)+(k-1)*surf.vox(3);
0035 end
0036 
0037 return
0038 end
0039