Plotting Matrix points: 2

Given a matrix:

B

ans =

   30.7805   28.7527   25.7110   23.6832   19.6268   17.5949   14.5547   11.5147    8.4725    5.4313
   29.7667   27.7333   24.6923   21.6549   18.6114   15.5708   12.5285    9.4806    7.4582    4.4159

B.'

ans =

   30.7805   29.7667
   28.7527   27.7333
   25.7110   24.6923
   23.6832   21.6549
   19.6268   18.6114
   17.5949   15.5708
   14.5547   12.5285
   11.5147    9.4806
    8.4725    7.4582
    5.4313    4.4159

I am trying to plot the data as shown in this image:

http://postimage.org/image/2wwighvs4/

I am trying to plot the 1st column as the orange points and the 2nd column as the blue points. The time between the points form a small box. The only axes I'm interested in is the X which will be composed of the overall time of the video. I am attempting to do this in a GUIDE axes. Eventually I want the user to be able to select the points and add labels.

Any advice in accomplishing this will be greatly appreciated!

Answer 1

[Paulo Silva]

a =[30.7805   29.7667
   28.7527   27.7333
   25.7110   24.6923
   23.6832   21.6549
   19.6268   18.6114
   17.5949   15.5708
   14.5547   12.5285
   11.5147    9.4806
    8.4725    7.4582
    5.4313    4.4159]
axis([0,max(a(:))+max(a(:))/5,0,2])
hold on
plot(a(:,1),1,'pb')
plot(a(:,2),1,'pr')
h=0.02;y=1;
arrayfun(@(n)rectangle('EdgeColor','y','Position',...
[min([a(n,1) a(n,2)]),y-h,abs(a(n,1)-a(n,2)),2*h]),1:size(a,1))
%with numbers if you want them:
arrayfun(@(n)text(min([a(n,1) a(n,2)]),y+2*h,...
num2str(size(a,1)-n+1)),1:size(a,1))

[B_Richardson]

wow... Theres alot going on here!

[Fangjun Jiang]

+1, Paulo! I admire, but, an overkill!

[Paulo Silva]

No big deal, I'm not even sure about the need of the arrayfun for the rectangle, I tried just with the rectangle but it didn't work.

[Fangjun Jiang]

I mean, what about axis([0,max(a(:))+max(a(:))/5,0,2]). I am scratching my head :).

[Paulo Silva]

max(a(:)) So the axis can catch all the action (plotted values)

just max(a) gives the row values where the maximum is so I put all elements from a in a column and max returns just one value

+max(a(:))/5 To give some space between plotted values and axis limit

[Oleg Komarov]

After the stars to plot the rectangles:

x = [a(:,[2 2 1 1 2]).'; NaN(1,size(a,1))];

y = [1.02 .98 .98 1.02 1.02 NaN];

line(x(:).',repmat(y,1,size(a,1)),'Color','y')

[Fangjun Jiang]

Okay, Paulo. Thanks for clarification. I mis-read the parenthesis thus had a different guess. 1.2*max() might be easier on the eyes.

[B_Richardson]

i'm still kinda lost...I see it works but I kinda need at least some understanding as to how it works. And just to clarify (and hopefully make it simpler) I dont really need the stars! lol I just put them there to clarify the starts and stops for you guys! (since at first nobody understood what I was trying to do!) I already have the data (start and stop). Whats more important was displaying the range (the box) of each start and stop.

[Paulo Silva]

it's simple, what don't you understand? did you check the functions on the MATLAB documentation?

[Oleg Komarov]

My solution with line alone simply emulates a human hand. Take a piece of paper and try to draw a rectangle, you will start from upper-left, go one down, one right, one up, and one left to close the rectangle. Now you have to lift your hand and go to the next one, I use NaNs to break the line.

Try to visualize the input with a small "a", with say 2 starting/ending points and see what happens.

[Fangjun Jiang]

If you don't want the star, you just need to modify the plot() line. Help plot will show you different color, marker, and line style. Paulo uses rectangle() to draw the box. Oleg uses line() to draw the box. Mine uses the line width to fake the box. If you set the width bigger, it's pretty good. set(h,'LineWidth',8,'color','red')

[B_Richardson]

I see. I took a break from the code (working on my research poster). I'm going to try and implement this in my final design next week. Thank you all for your help and consideration!

Answer 2

[Fangjun Jiang]

B=[30.7805   28.7527   25.7110   23.6832   19.6268   17.5949   14.5547   11.5147    8.4725    5.4313
   29.7667   27.7333   24.6923   21.6549   18.6114   15.5708   12.5285    9.4806    7.4582    4.4159];

h=line(B,zeros(2,10));
hold on;
plot(B(1,:),zeros(10,1),'y*');
plot(B(2,:),zeros(10,1),'bo');
set(h,'LineWidth',2,'color','red')

[B_Richardson]

Can you explain how this works?

[B_Richardson]

I am also looking at your other example:

line(B',zeros(2,10));

hold on;

plot(B,zeros(10,2),'o');

But I cant get it to work?

[Fangjun Jiang]

Well, you changed the size of your B from previous one (10x2 vs. 2x10).

[B_Richardson]

I see. I was confused as to how the plot function would accept the matrix. In reality, it doesnt matter to me whether it is 10 by 2 or 2 by 10. As long as the points are in the correct order (start/stop)

Answer 3

[B_Richardson]

I see that it works, but i'm trying to translate it into guide

[Jan]

I do not see a reason to translate this to a complicated GUI, which would create the same code in the ideal case.

[B_Richardson]

Im not sure if i understand? The matrix B is created in a GUI from user input. I am then, going to plot this data in axes in the GUI. Do this make sense?

[Fangjun Jiang]

Then, you'll probably have a button in your GUIDE GUI. In its callback function, you'll get the data B, create an axes and the use the above code to create the figure.