Matlab not running? No errors

sig = 1; % Source strength % GRID: x = -150:.02:150; y = 0:.02:100; for m = 1:length(x) for n = 1:length(y) xx(m,n) = x(m); yy(m,n) = y(n); % Velocity potential function: phi_Source(m,n) = (sig/4/pi) * log(x(m)^2+(y(n)+.01)^2); % Stream function: psi_Source(m,n) = (sig/2/pi) * atan2(y(n),x(m)); end end % Plots % Source at origin of coordinat systex: contour(xx,yy,psi_Source,(-0.5:.5:5),'k') hold on contour(xx,yy,phi_Source,10,'r') legend('streamlines' ,'potential') title(' Source at origin') axis image hold off

[Eric]

Here is the code properly formatted (you're welcome, Ricardeo):

 sig = 1;
 % Source strength
 % GRID:
 x = -150:.02:150;
 y = 0:.02:100;
 for m = 1:length(x)
   for n = 1:length(y)
     xx(m,n) = x(m);
     yy(m,n) = y(n);
     % Velocity potential function:
     phi_Source(m,n) = (sig/4/pi) * log(x(m)^2+(y(n)+.01)^2);
     % Stream function:
     psi_Source(m,n) = (sig/2/pi) * atan2(y(n),x(m));
   end
 end
 % Plots 
 % Source at origin of coordinate system:
 contour(xx,yy,psi_Source,(-0.5:.5:5),'k')
 hold on
 contour(xx,yy,phi_Source,10,'r')
 legend('streamlines' ,'potential')
 title(' Source at origin')
 axis image
 hold off

ProTip: Check out meshgrid to transform it into:

 [yy xx] = meshgrid(y,x);
 phi_Source = (sig/4/pi) .* log(xx.^2+(yy+0.01).^2);
 psi_Source = (sig/2/pi) .* atan2(yy,xx);

and avoid for loops.

Answer 1

[Image Analyst]

It runs for me. Takes like 25 minutes though. What is your question?

See this link: http://www.mathworks.com/matlabcentral/answers/13205#answer_18099

Answer 2

[Eric]

Be patient, it just takes a long time to display the plots. For me it took about 2 seconds for the contour functions to return and about 86 seconds for the figure to display. You may want to look into alternative ways to plot, or ways to reduce the number of elements plotted, if you desire speed.