Lax Wendroff and SWE

Hi i am looking to appoximat a depth derived 1d continuity equation to model the break of a dam at different points in time, i have been told to use the lax wendroff scheme, i belive i have programmed this okay but as to using it to solve the 1d continuity equation im not sure what to do?

The equation for the continuity that i have come up with is [h ;uh] + [uh; hu^2++1/2gh^2] = [0; -ghB] (i was actually moe lucky to stumble across it than work it out)

any help would be appreciated, preferable just a few pointers, i would like to try and do it myself :)

thanks kyle

the lax wendrof code im using is as below:

function lax

close all clc clear all

%intial values

ntime = 50; dt=0.00050; nx=100; time = 0; a=2;output=0.05;

%step size calculation dx= (1/nx);

%create size of u_int vector

u_int = zeros(nx,2);

%create little u_int vector for the initial values of height begining and %end depending which val

ue of A is used

u_int(nx,2) = 1;

u_int(1,1) = 1;

%loop for the two directions needed

for vec = 1:2

    %centered

    U=zeros(nx,1);%initial size of matracies

F=U;

update = U;

%determine which vector of u_int to use and wether A is posative or %negative

if vec == 1;

U(1,vec)=u_int(1,vec);

A=a;

else

    U(nx,vec)=u_int(nx,vec);
    A=-a;
end

%main calculation loop for specified time

for p = 1:ntime;

    if(time + dt>output); dt=output-time;%if to jump out of time loop at given time
    end
        coeff = (dt/dx);%calculate coeff

    for i = 1:(nx-1)%int calcs for next step (lax step<<<)
        F(i+1,vec) = A*((U(i,vec) + U(i+1,vec))/2);
    end
    for i = 2:(nx-1)%true calcs back at step 2 find step 1 ect...
        update(i,vec) = U(i,vec) - coeff*(F(i+1,vec)-F(i,vec));
    end
    for i = 2:(nx-1)
        U(i,vec) = update(i,vec);
    end
    time = time + dt;
if time == output
break  
end

end

figure(vec) plot(U(:,vec),'r');grid on;legend('centered') hold on end

end