%ENG_KRIGE is now modified to compute relevant inputs for    
%        kriging the north carolina ozone data.


%NOTE: Requires that 'aqozone.txt' be loaded in the workspace.

clear('X0','L0','X1','L1');

clear('x','y','z','L','X') ;

z = aqozone(:,3); %1992 nc air quality ozone data

%Transform Sample Locations

x = aqozone(:,1);
y = aqozone(:,2);

L = aqozone(:,1:2);

X(:,1:2) = L;
X(:,3) = x.^2 ;

%SAMPLE DATA

X0 = X ;
L0 = L ;

%Now form grid locations

clear('x','y','X','s1','u1','U1',...
      's2','u2','U2','S'); 

s1 = [-85:0.2:-75]';
u1 = length(s1);
U1 = ones(u1,1);

s2 = [32:0.2:38]';
u2 = length(s2);
U2 = ones(u2,1);

S(:,1) = kron(s1,U2);
S(:,2) = kron(U1,s2);

x = S(:,1) ;
y = S(:,2) ;

X(:,1:2) = S;
X(:,3) = x.^2 ;


%GRID DATA

X1 = X ;
L1 = S ;