interval = 0.05;
xmin = -5.0001;
xmax = 5;
ymin = -5.0001;
ymax = 5;

[x,y] = meshgrid (xmin:interval:xmax, ymin:interval:ymax);
U = 1;
a = 1;
%GAMMA = 100;

%singularitets-drap
cutoff = 10;

clear F

%Vi er late og gidder ikke gjøre om formel fra polare koordinater
r       = sqrt ((x.*x) + (y.*y));
tetha   = atan2 (y, x);

frameindex = 1;

for t = 5:0.1:20
    GAMMA = t
    psi = U.*(-r + (a.*a)./r).*sin(tetha) - (GAMMA/(2*pi)).*log(r./a);

    %Drep singulariteten!
    for j = 1:((ymax-ymin)*(1/interval)) %y-pos
      for i = 1:((xmax-xmin)*(1/interval)) %x-pos
        if psi(j,i) > cutoff
          psi(j,i) = cutoff;
        end
        if psi(j,i) < -cutoff
          psi(j,i) = -cutoff;
        end
      end
    end
    contour (x,y,psi,30)
    hold on
    if GAMMA > 4*pi*U*a
      rs = (1 + sqrt(1 - (4*pi*U*a/GAMMA)^2))*GAMMA/(4*pi*U*a);
    else
      rs = a;
    end
    psis = -U*(-rs + (a*a)/rs) - (GAMMA/(2*pi))*log(rs/a)
    contour (x,y,psi,[0, psis],'k')%,'LineWidth',2)
%    contour (x,y,psi,[0],'LineWidth',2)
    text(-4,4, sprintf('GAMMA/4*pi*a*U = %f', GAMMA/(4*pi*a*U)));
    hold off
    F(frameindex) = getframe;
    frameindex = frameindex + 1;
end

'Nå kan du kjøre movie(F,antallganger,FPS)'