MATLAB: How to stop patch from making the squares into rectangles

patch

Hi all,

I am trying to call patch multiple times to draw multiple squares. I am using patch because even though I am currently drawing squares, I am planning to draw a more complex polygon later on.

However I am facing a problem: even though the coordinates should create a 1×1 size square, matlab is stretching my polygon and drawing a rectangle. Additionally, I want my squares to be bigger, but changing my 1×1 square to a 2×2 square does not change the size. How can I adjust the polygon drawn by patch? It's ok for my squares to resize if I maximize/ stretch the figure, but I want some control over the initial size and shape.

Here is some code which produces the unexpected result:

x1 = [0 1 1 0];
y1 = [0 0 1 1];
x2 = [1.2 2.2 2.2 1.2];
y2 = [0 0 1 1];
x3 = [2.4 3.4 3.4 2.4];
y3 = [0 0 1 1];
patch(x1,y1, 'red')
patch(x2,y2, 'blue')
patch(x3,y3, 'green')

Here is the figure:

I can tell by reading the axes of the chart that my 'squares' are 1×1, but the figures drawn are rectangles. I want to make them squares.

I would really appreciate help with this. I have tried both 'truesize' and set(gcf,'Resize','off') but they stop the figure from resizing and do not force my squares to be 1 pixel by 1 pixel as I expected.

Best Answer

Hi,

you can add to your code the following line:

axis equal

In this way you obtain the following result:

You can see:

https://www.mathworks.com/help/matlab/ref/axis.html

https://www.mathworks.com/help/matlab/ref/matlab.graphics.axis.axes-properties.html

to have control on axes appearance.

Hope this helps.

Related Solutions

MATLAB: How to keep axes on top of uipanels

I was able to figure out the answer myself. The simple solution is to use Annotations:

https://uk.mathworks.com/help/matlab/ref/annotation.html

Specifically a rectance annotation:

https://uk.mathworks.com/help/matlab/ref/matlab.graphics.shape.rectangle-properties.html

This has a property called FaceAlpha which changes its transparency and these annotations can be placed on uipanels of figures. Below is the code that works as I desire:

F = figure('menubar','none','numbertitle','off','Color','w');
P = uipanel('Parent',F,'BorderType','none','BackgroundColor','g',...
                'Units','normalized','Position',[0 0 1 1]);
A = axes('Parent',P,'GridColorMode','manual','GridColor','k',...
            'XGrid','on','YGrid','on','GridLineStyle','--','NextPlot',...
            'add','Units','normalized','Position',[0 0 1 1]);
T = 1:1:10;
V = 10*rand(1,10);
plot(T,V,'Parent',A,'Color','r');
An = annotation(P,'rectangle',[0.25 0.25 0.5 0.5],'FaceColor','b',...
                'FaceAlpha',0.5,'LineStyle','none');

And the outcome of this code is:

This is exactly what I need, a semi-transparent thing on top of axis to signify the area of plot that will be analysed.

MATLAB: Is part of the graph cut off in MATLAB R2014b

Starting in R2014b, graphics objects do not extend beyond the axes boundaries. Objects are clipped to the six sides of the axes box defined by the axes limits. For example, MATLAB® does not display the peaks of this surface that extend beyond the specified z-limits.

surf(peaks);
zlim([-3,4.5]);

In R2014a and earlier, MATLAB uses a different technique to clip objects. Instead of clipping to the axes limits, MATLAB clips to the smallest 2-D rectangle that encloses the axes. For example, in previous releases, the same surface plot extends beyond the specified z-limits. The red rectangle indicates the boundaries used for clipping.

surf(peaks);
zlim([-3,4.5]);

The axes and individual objects in the axes have a 'Clipping' property that controls the clipping behavior. By default, this property is set to 'on'. To disable clipping, set the 'Clipping' property to 'off'.

If the 'Clipping' property for the axes is 'on', then each individual object in the axes controls its own clipping behavior. To disable clipping for all objects in the axes, set the 'Clipping' property for the axes to 'off'.

For example, disable the clipping for all objects in the axes by setting the Clipping property of the axes to 'off'.

surf(peaks);
zlim([-3,4.5]);
ax = gca;
ax.Clipping = 'off';

The new 'ClippingStyle' axes property introduced in R2014b controls the technique used to clip objects. Set this property to one of these values:

· '3dbox' — Clip objects to the six sides of the axes box defined by the axes limits. This is the default value.

· 'rectangle' — Clip objects to the smallest 2-D rectangle that encloses the axes in any given view.

To get the same style of clipping used in R2014a and earlier, set the ClippingStyle to 'rectangle'.

surf(peaks)
zlim([-3,4.5]);
ax = gca;
ax.ClippingStyle = 'rectangle';
<<http://www.mathworks.com/matlabcentral/answers/uploaded_files/19112/1cc4c5615fe2b461c6063e9d548acd98.png>>

Best Answer

Related Solutions

MATLAB: How to keep axes on top of uipanels

MATLAB: Is part of the graph cut off in MATLAB R2014b

Related Question