[x,y] = meshgrid(0:0.1:5,0:0.1:5);
alpha =10;
U=1;
startx = 0.1:0.1:5;
starty = ones(size(startx));
for i =1:length(x)
for j=1:length(y)
U=U+1;
u(i,j)=U*cos(alpha*(pi/180)); % use for loop indices
v(i,j)=U*sin(alpha*(pi/180));
end
end
figure
quiver(x,y,u,v)
use for loop indices
