refreshdata loop issues

Hello, I am a beginner using Matlab R2011a to try to create a simulation which updates a plot in real time. In a different function I import a 100x2x100 matrix which has x and y coordinates and various frames in time. (matrix O) The matrix is solve earlier but I try to display it by refreshing the data at intervals of 0.5 seconds.

function refreshd(O)

lim = max(O(:,1,1)); % boundaries of plot axis

S = size(O,3); % maximum time frames
a = O(:,1,1); % x coordinates (time 0)
b = O(:,2,1); % y coordinates (time 0)
h = plot(a,b,'o','MarkerEdgeColor','g','MarkerFaceColor','g');
set(gca,'Color','k');
set(h,'XDataSource','a','YDataSource','b');

for i = 2:S
    pause(0.5)
    a = O(:,1,i); % x coordinates (time i)
    b = O(:,2,i); % y coordinates (time i)
    refreshdata
end

The original plot displays perfectly, and if I manually plot the other times in debug they also display nicely. When I use refreshdata however it just displays a distorted single line which is incorrect. Even if I put refreshdata immediately after I plot the time 0 coordinates (before updating any data) i get the same distorted result which doesn't make sense to me. I have been able to make examples of this work in the workspace but for some reason not here.

Answer 1

[Oleg Komarov]

Drop:

set(h,'XDataSource','a','YDataSource','b');

and use in the loop:

set(h,'xdata',O(:,1,ii),'Ydata',O(:,2,ii))

note i stand for irrational so don't use it.

Answer 2

[Walter Roberson]

The refreshdata documentation says, "Note that the variable assigned to the data source property must be in the base workspace." This applies unless you use

refreshdata(h, 'caller')