function Bs=cinit(sys,data,snorm)%CINIT forms the matrix containing the control point position, orientation and%geometry. This is an internal function used by CIRCAL, CIRCALW, and EXTCAL.%   Version 3.0  10-17-00%   Janne Heikkila, University of Oulu, Finlandn=size(data,1);r=sys(6);v3=snorm;vv=randn(3,1); vv=vv/norm(vv);v2=ones(n,1)*vv'-v3*[vv vv vv].*v3;nnn=sqrt(sum(v2'.^2))';v2=v2./[nnn nnn nnn];v1=[v2(:,2).*v3(:,3)-v2(:,3).*v3(:,2) ...    v2(:,3).*v3(:,1)-v2(:,1).*v3(:,3) ...    v2(:,1).*v3(:,2)-v2(:,2).*v3(:,1)];x=data(:,1);y=data(:,2);z=data(:,3);B11=x.^2-r^2*(v1(:,1).^2+v2(:,1).^2);B12=x.*y-r^2*(v1(:,1).*v1(:,2)+v2(:,1).*v2(:,2));B13=x.*z-r^2*(v1(:,1).*v1(:,3)+v2(:,1).*v2(:,3));B22=y.^2-r^2*(v1(:,2).^2+v2(:,2).^2);B23=y.*z-r^2*(v1(:,2).*v1(:,3)+v2(:,2).*v2(:,3));B33=z.^2-r^2*(v1(:,3).^2+v2(:,3).^2);Bs=[B11 B12 B13 x B12 B22 B23 y B13 B23 B33 z x y z x*0+1]';