function y=ihaar1d(y)
    m=2;
    while(m<=length(y))
        y(1:m)=isplithm(y(1:m));
        m=m*2;
    end
end
function z=isplithm(z)
    n=length(z)/2;
    e=(z(1:n)+z(n+1:2*n))/sqrt(2.0);
    o=(z(1:n)-z(n+1:2*n))/sqrt(2.0);
    z(1:2:2*n-1)=e;
    z(2:2:2*n)=o;
end
