%DGL = @(x,y) sin(x).*(y+1)
DGL = @(x,y) sin(x)
delta = 0.2;
[X Y] = meshgrid(0:delta:6.5, 0:delta:2.5);
dY = DGL(X,Y);
dX = ones(size(dY));
L=sqrt(1+dY.^2);
figure
quiver(X, Y, dX./L, dY./L, ':' );

hold on
xL = xlim;
yL = ylim;
line([0 0], yL, 'Color', 'black');  %y-axis
line(xL, [0 0], 'Color', 'black');  %x-axis
scatter(0,0, 200, 1, 'filled');

%sol = dsolve('Dy = sin(x)*(y+1), y(0) = 0','x'); 
sol = dsolve('Dy = sin(x), y(0) = 0','x'); 
pretty(sol)
fplot( sol, [0, 7])

[xe, ye] = odeEULER_CAUCHY( DGL, 0,7,1,0 );
plot(xe, ye, 'linewidth', 2 )
scatter(xe, ye, 'linewidth', 2)

[xe, ye] = odeEULER_verb( DGL, 0,7,1,0 );
plot(xe, ye, 'linewidth', 2)
scatter(xe, ye, 'linewidth', 2)