How do I set Transparency of area plot in R2014b?

Hi! I've recently migrated to R2014b and I'm having troubles setting the transparency value of an area plot which worked fine before.
Time = [1:1:10];
y = Time;
recess = [2,0; 2,1; 4,1; 4,0; 6,0; 6,1; 8,1; 8,0]
[AX, LINE1, AREA]= plotyy(Time,y,recess(:,1),recess(:,2),@plot,@area);
%set properties of lines and area
set(LINE1,'Linewidth',2)
set(AREA,'EdgeColor', 'none'); % make area's edge invisible
set(get(AREA, 'Children'), 'FaceAlpha', 0.3); %here is the problem - I cannot use FaceAlpha in the same way as before anymore
Please let me know if you have an idea how to circumvent this problem. I'm grateful for any advice. Thank you!!

Answers (2)

Jacob D
Jacob D on 28 Aug 2015
Edited: Jacob D on 28 Aug 2015
Here is a solution to your problem. It allows transparent area plots in R2014b and newer. =] I only replaced your last line of code with the last three lines shown here:
Time = [1:1:10];
y = Time;
recess = [2,0; 2,1; 4,1; 4,0; 6,0; 6,1; 8,1; 8,0]
[AX, LINE1, AREA]= plotyy(Time,y,recess(:,1),recess(:,2),@plot,@area);
%set properties of lines and area
set(LINE1,'Linewidth',2)
set(AREA,'EdgeColor', 'none'); % make area's edge invisible
% Make area transparent
drawnow; pause(0.05); % This needs to be done for transparency to work
AREA.Face.ColorType = 'truecoloralpha';
AREA.Face.ColorData(4) = 255 * 0.3; % Your alpha value is the 0.3
After creating the plot you may be able to use h = findobj('Type','patch'); to get handles of all patch objects, then set facealpha of h.

4 Comments

Hi Chad, thanks for your fast reply. I've tried your suggestion, but findobj(AREA,'Type','patch') just returns a 0x0 empty GraphicsPlaceholder array. Under properties of AREA children = [], so no wonder I can't access FaceAlpha anymore. Is there another way to change the transparency property of an area in R2014b?
Hi Julia, I don't think plotyy is returning correct AREA handles. That's why I suggested using findobj without using AREA as an input to return all visible patch objects. If other patch objects exist you may need to manually determine which handles in h are of interest to you.
Hi Chad, I agree with Julia: findobj no longer works. Probably due to graphics system update in R2014b.
h = findobj('Type','patch')
no longer works. Just like
h = findall(gca,'Type','patch')
.
So.. any luck with looking for answer?
This made me sad.

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Asked:

on 27 Dec 2014

Edited:

on 28 Aug 2015

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