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Topic: problem with matrix
Replies: 14   Last Post: Apr 8, 2013 4:47 PM

 Messages: [ Previous | Next ]
 Bruno Luong Posts: 9,822 Registered: 7/26/08
Re: problem with matrix
Posted: Apr 8, 2013 4:44 PM

zack00 <p.hilovsky@gmail.com> wrote in message <f42ca2ca-d79b-477e-a335-b3a5d6ccf5e6@googlegroups.com>...
> I have a zero matrix with 100 collumns. I save there ploting signal from infinity loop.
> i want save only last 100 collumns..Start running plot and save data to matrix.
> When the matrix is filled delete first collumn and shift to left and save the last value.
>
> Can you help me with this problem?

Try this:

f = (1+rand(1,3));
a = 1+rand(1,3);
tfun = @(t) a.*sin(t.*f);

fig = figure(1);
clf(fig);
ax = axes('Parent', fig);

t = 0;
dt = 0.01;

i = 1;
filled = false;
m = length(f);
n = 100;
ft = nan(n,m);

h = plot(ax, ft);
axis(ax, [0 n -2.5 2.5]);
set(ax, 'Xtick', []);
while true
t = t+dt;
i = mod(i,n) + 1;
ft(i,:) = tfun(t); % Put your function here
filled = filled || i == 1;
if filled
idx = [i+1:n 1:i];
else
idx = 1:i;
end
for k=1:m
set(h(k), 'YData', ft(idx,k));
end
pause(0.01);
end

% Bruno

Date Subject Author
4/8/13 zack00
4/8/13 dpb
4/8/13 Bruno Luong
4/8/13 zack00
4/8/13 dpb
4/8/13 dpb
4/8/13 dpb
4/8/13 dpb
4/8/13 Bruno Luong
4/8/13 dpb
4/8/13 Bruno Luong
4/8/13 dpb
4/8/13 zack00
4/8/13 dpb
4/8/13 Bruno Luong