Free hand drawing in Matlab with output is XY coordinate of trajectory.

How i can free draw any trajcetory with the output is the XY coordinate of trajectory like in the picture. I just try to find in the answer in form but did no find any answers satisfiing the requirement. Tks you for any answer.

Answer 1

[Adam Danz]

This might be what you're looking for. ginput() allows you to click on a graph as many times as you'd like and it returns a 2-column matrix of x,y coordnates where you clicked.

Demo 1

Run this, click around the axes, press Enter to see where you clicked. xy will be the coordinate of your clicks.

figure
xy = ginput(); % now click as many coordinates as you'd like then press Enter when finished. 
plot(xy(:,1), xy(:,2), 'bo', 'MarkerSize', 8, 'MarkerFaceColor', 'b'); 

Demo 2

This version plots as you click instead of plotting at the end. Press Enter to stop. xy will be the coordinate of your most recent click.

figure
axh = axes;
hold(axh, 'on')
xy = [0,0];
while ~isempty(xy)
    xy = ginput(1);
    if ~isempty(xy)
        plot(axh, xy(1), xy(2), 'bo', 'MarkerSize', 8, 'MarkerFaceColor', 'b');
    end
end

[tien dang]

many thank you about your answer.

Answer 2

[Peter Seibold]

Another demo that stores the xy values:

disp('click inside figure')
disp('hit "return" button to finish')
figure(1)
clf
axh = axes;
hold(axh, 'on')
xlim([0,2])% change the limits to your requirements
ylim([0,1])% change the limits to your requirements
grid on
xyTemp = [0,0];
xy=xyTemp;
k=0;
while ~isempty(xyTemp)
    xyTemp = ginput(1);
    if ~isempty(xyTemp)
        plot(axh, xyTemp(1), xyTemp(2), 'bo', 'MarkerSize', 6, 'MarkerFaceColor', 'b');
        k=k+1;
        xy(k,:)=xyTemp;
    end
end
hold(axh, 'off')
figure(2)
plot(xy(:,1),xy(:,2),'.-b')
grid on
disp('finished')
disp('Previous to a second run you may resize the figure to your requirements')