MATLAB: How to plot a combined of attached photos (triangular domain)

edgeslinspacemeshgridsurftriangletriangular domaintriangular meshgrid

Hi friends

I plotted some figures using followin code with several Delta:

delta = 0.05;
[z, y] = meshgrid(0:delta:0.8660254, -0.5:delta:0.5);
s = (0.1069166660e0 .* (0.36e2 .* (z - sqrt(0.3e1) ./ 0.2e1) .^ 2 .* y .^ 2 + (0.3e1 .* y .^ 2 - z .^ 2 - 0.2e1 .* (z - sqrt(0.3e1) ./ 0.2e1) .* z) .^ 2) ./ (0.370370196e0 .* (z - sqrt(0.3e1) ./ 0.2e1) .* (0.3e1 .* y .^ 2 - z .^ 2) + 0.1e1) + 0.1e1) ./ (0.370370196e0 .* (z - sqrt(0.3e1) ./ 0.2e1) .* (0.3e1 .* y .^ 2 - z .^ 2) + 0.1e1);;
s(y<-0.5773502692.*z) = NaN;
s(y>0.5773502692.*z) = NaN;
surf(z, y, s,'FaceColor','interp','FaceLighting','phong');

the following figures have been plotted using delta=0.005, 0.005, 0.05 and 0.01, respectively.

As it is obvious, the boundary of triangular domain is good in 1st and 2nd figures but their Edges is so high which if i show them, the figure's color will be black!

about the third figure, the number of edges is good but its boundary is so bad.

I want to generate the combining of 1st figure and the figure with similar edge density to 3rd figure.

If you know please answer to my question as simple as you can.

Thanks a lot

Best Answer

You could try plotting both of them on the same axes:

funZY = @(d) meshgrid(0:d:0.8660254, -0.5:d:0.5);
funS = @(z,y) (0.1069166660e0 .* (0.36e2 .* (z - sqrt(0.3e1) ./ 0.2e1) .^ 2 .* y .^ 2 + (0.3e1 .* y .^ 2 - z .^ 2 - 0.2e1 .* (z - sqrt(0.3e1) ./ 0.2e1) .* z) .^ 2) ./ (0.370370196e0 .* (z - sqrt(0.3e1) ./ 0.2e1) .* (0.3e1 .* y .^ 2 - z .^ 2) + 0.1e1) + 0.1e1) ./ (0.370370196e0 .* (z - sqrt(0.3e1) ./ 0.2e1) .* (0.3e1 .* y .^ 2 - z .^ 2) + 0.1e1);
funN = @(z,y) y<(-0.5773502692.*z) | y>(0.5773502692.*z);
[surfZ,surfY] = funZY(0.0005);
[gridZ,gridY] = funZY(0.05);
surfS = funS(surfZ,surfY);
gridS = funS(gridZ,gridY);
surfS(funN(surfZ,surfY)) = NaN;
gridS(funN(gridZ,gridY)) = NaN;
surf(surfZ, surfY, surfS,'FaceColor','interp','FaceLighting','phong','EdgeColor','none');
hold on
surf(gridZ, gridY, gridS,'FaceColor','none','FaceLighting','phong');
view(43,20)

Related Solutions

MATLAB: With what command i can change the width of contours created with SURFC from the beginning

The property is LineWidth, but things are a little tricky with surfc. The surfc command turns around and calls surf and contour. It is going to pass all of the property/value pairs you give it to the surf command, not the contour command. That means that if we do this:

surfc(peaks,'LineWidth',4)

We'll get wide lines on our surface, rather than on our contour.

The easiest way to set properties on the contour object is to get the return value from surfc.

h = surfc(peaks)

This should say something like this:

h = 
2x1 graphics array:
Surface
Contour

That's saying that h is an array of two graphics objects. The first is the surface and the second is the contour. That means that we can do things like this:

h(2).LineWidth = 4

MATLAB: Shading error when using surf to plot symmetric data set

Hi Lucas,

You are correct, this behavior is reproducible and can be explained as follows: The 'Facecolor' property of surf (patch object) can be set to 'none', 'flat' and 'interp': link to the documentation. The default value of the 'FaceColor' is 'flat' which uses uniform face colors. The color data at the first vertex determines the color for the entire face (and hence one quadrant was red since its first vertex had value '1'). You cannot use this value when the 'FaceAlpha' property is set to 'interp. Find below the same surf plot with 'FaceColor' property being set to 'interp':

>> s = surf(x,y,z);
>> set(s,'FaceColor', 'interp');

Now if we rotate the plot appropriately we can see that each quadrant is made up of two triangles (since all the 4 points that make up the patch are not co-planar, so the patch needs to be drawn as two triangles). You can also notice how the triangles are arranged/joined differently in the lower left and lower right quadrants (the demarcation is shown by red and green lines respectively):

>> l1 = line([0 1],[-1 0],[0 0],'Color','green');
>> l2 = line([-1 -0],[-1 0],[0 1],'Color','red');

The order and the way in which the triangles are created is decided by the 'surf' command. We can explicitly define the order of the faces/triangles, for example in the following way (though it would be a little tedious):

>> [X,Y] = meshgrid(-1:1,-1:1);
>> Z = [0 0 0; 0 1 0; 0 0 0];
>> V = [X(:) Y(:) Z(:)]; % vertices in 3D 
>> F = [2 5 3; 3 5 6; 6 5 9; 9 5 8; 8 5 7; 7 5 4; 4 5 1; 1 5 2]; % order of the vertices making up the patch
>> p = patch('Faces',F,'Vertices',V); 
>> set(p,'FaceVertexCData',Z(:)); 
>> set(p,'FaceColor','interp');

I believe this generates the figure you were expecting in your problem.

Best Answer

Related Solutions

MATLAB: With what command i can change the width of contours created with SURFC from the beginning

MATLAB: Shading error when using surf to plot symmetric data set

Related Question