Is it possible to extract the coordinate of surface vertices in the fimplicit3 function in Matlab?
Couldn't found how to do with fimplicit3, but it easier to extract vertices and faces from a surface using isosurface function.
One can follow this tutorial: Implicit curves and surfaces sith Isosurface
I need to ask help in plotting a 3D volume in MATLAB. My data set includes the X, Y, Z coordinate and corresponding intensity value, V.
I was using pcolor (X,Y,V) and shading interp while i was doing the 2D images but then I got stuck when I am about to create the 3D images. I have tried scatter3, smooth3 and slice but it seems it does not fit the function I need.
My goal is to plot the 3D grid with the corresponding intensity value per coordinate and apply shading interp between these points.
I am really new in 3D plotting and I would really appreciate any help in achieving my goal. Thank you so much!
Here are some example of images that I am trying to create
(source: ndt.net)
(source: www.bam.de)
I have a solution for your first example, in which you show three cross-sections of the volume data. With this solution you can essentially plot several pcolor with different orientations, in one same 3D figure.
First, you need the data for the different slices. This is exactly what you had when you did pcolor(X,Y,V) to plot the cross section in 2D, where X, Y and V are two dimensional matrices. You will also need to create a matrix Z with the z-position of the slice (e.g. Z = zeros(size(X)) + z0). Then you use the command surface(X,Y,Z,V) to plot the cross section image in 3D, where X,Y,Z are the positions, and V is the color (value of the function).
Repeat this procedure for all the other slices, using appropriate X,Y,Z,V matrices for each slice. For slices oriented on other axes you will have to define X,Y,Z accordingly. Remember to use "hold on" after the first surface command, so that all the slices are plotted.
Example:
surface(X1,Y1,Z1,V1); shading interp; hold on
surface(X2,Y2,Z2,V2); shading interp;
surface(X3,Y3,Z3,V3); shading interp;
colormap(jet(2048)); caxis([0,3]); % color axis colormap and scaling
axis equal; xlabel('X'); ylabel('Y'); zlabel('Z') % X,Y,Z scaling and label
Result figure here:
I've got multiple vectors of which I would like to plot seperate histograms in the same figure. However, if I plot all histograms in the same 2D plot, the results become hard to interpret/distinguigh. Therefore I would like to plot them (detached) in 3D.
All I have right now is the following:
hist(A)
hold on
hist(B)
hist(C)
holf off
checkout bar3 for 3D bar plots.
I have dataset of XYZ as the coordinates and V as the value at each point (100x4 matrix).
I plot the 3D surface using patch. (by faces & vertices)
How can I plot the contour lines of V (NOT Z) over the 3D surface !?
( The Contour3 function plots 3D contour lines of Z ; But I need contour lines of V. )
Actually I want something like this or this.
Thanks a billion for your help.
Well actually I found out that the isosurface command is exactly what I want.
However, this command requires the V data to be a 3D matrix. But my V is a vector. And the data in it is completely non-uniform and irregular. Now here rises a new question :
How can I convert this non-uniform vector to a 3D matrix, so that it's ready to be used with isosurface command !!?
Please help me with this.
cont3d from MathWorks FileExchange is not exactly what you're looking for, but it may give you some ideas.
I have a 3D Matrix M(256x256x136) and each index(i,j,k) in M has a gray level value in it. I am interested in displaying M in some sort of a 3D plot in MATLAB, but am unable to do so. I cannot use plot3 because plot3 is for plotting points, not the values.
Thanks
If I understand your question correctly, you want to plot the 3D point cloud with i,j, and k as 3D coordinates and the gray level as the point value.
I would suggest using scatter3.
Sounds like you are looking for a volume renderer. For Matlab, you could try this one: Volume Render from Matlab Central
An isosurface plot might be useful as well.