How do I read a mesh file (.ply) and display it in Matlab?
Also, how can I change the camera viewpoint of said model?
Thanks
Go to this link : http://people.sc.fsu.edu/~jburkardt/m_src/ply_display/ply_display.m
and save this file.
The ply_display.m is a Matlab function (as opposed to a Matlab script). A Matlab function will usually need an input. You can call the ply_display function by being in the same folder as the .m file. You call it this way :
ply_display('file.ply')
%where
%'file.ply' is the name of the file
I see that this question was raised 2 years ago. But MATLAB R2015a seems to have what you wanted:
ptCloud = pcread(filename)
http://www.mathworks.com/help/vision/ref/pcread.html
Related
This question already has answers here:
How to read images from folders in matlab
(3 answers)
Closed 6 years ago.
I want to load an image in MATLAB :
f=imread('fulldirectory');
m=size(f);
printf('m');
MATLAB shows me this error when I attempt to run it:
"Error using imread (line 349)"
Can anyone help me?
Imread function needs a file format, e.g., jpg.
You can use one of the following MATLAB codes.
f = imread('ngc6543a.jpg');
f = imread('ngc6543a', 'jpg');
Also, just omit the semicolon (;) from your second line of your codes, if you want to know the dimension of the image. MATLAB will display the size of the image.
m=size(f)
MATLAB has some test images such as ngc6543a.jpg and you can try my code in your MATLAB.
For matlab: Is there a way to write the value of a vector to a file that can later be opened and read by another matlab program?
Specifically: I have a matlab program that computes a binary-valued vector $zvector$ with 10^7 entries. I want to write $zvector$ as data to an output file so that it can be emailed and easily read as input to another matlab program. Ideally, the output file would be called “Output.m” and would look like:
zvector=[
0
1
1
…
0
1
];
I like the .m format because it is easy to use for matlab input. I have experimented with matlab’s write() and fwrite() commands, with no success. I observe that these generate files that cannot be easily read as matlab-recognizable inputs (at least, I do not know how to read from them). Is there a way to accomplish my goals? Thanks.
PS: I am interested in the easiest way. If this involves a different type of file format (not a .m format) that is fine. However, in that case, can you provide both the writing and reading commands? Thanks again.
Thanks to #edwinksl for pointing me in the right direction with MAT files. I do not know the accepted practice here, but in stackexchange math it is encouraged to answer your own question if a hint from comments got you all the way there. So I will answer my own question.
The Mat format does this well. Here are example script files for reading and writing in the Mat format (see also links in above comments for more documentation):
***Script file OutputTest.m:
filename = 'TestFile.mat';
TestVector=[1 1 0 1];
save(filename, 'TestVector');
***Script file IntputTest.m
filename = 'TestFile.mat';
file=load(filename);
z =file.TestVector;
z
I'm just starting to learn MatLab.
This is what I'd like to convert into MatLab code:
http://postimg.org/image/jqdvcrbod/
Since a lot of my variables are functions or other variables, does that mean that when I write them as functions in MatLab I have to save each of the functions as a separate file? Is there any other way? I don't want to end up with a million separate files, but as of right now, if I write more then one function in the editor, it starts getting confused and doesn't recognize the second function.
Also, is there a way to use actual symbols (like the square root symbol instead of writing "sqrt()") like in Mathematica? I feel like long equations (like the last one) are easier on the eye that way, but that's purely aesthetics.
Is there a way to have MatLab output unassigned variables? Like in Mathematica, if I have y(x) = 2x, if i don't put anything for x, it just outputs 2x.
One quick way to do is use a package in Mathematica called ToMatlab (I attached the download link). It is able to convert Mathematica symbol syntax to Matlab .m file.
Hope this would help.
Ok, so this question is related to my ongoing task of getting text data categorized, you can refer to this question for more details on how I approached this problem.
I used the standard matlab function "nctool" (neural clustering tool) to get my inputs organized on a plane of 10x10 SOM nodes. I also got the output of this map (i.e. which of my inputs ended up on which node) saved in to the "output" variable in my workspace.
I would now like to get this data out and see if I can write another script. I'm aware of the 'save' and some of the export functions in MATLAB, however it seems that MATLAB does not support ascii export of this variable since it is a sparse matrix.
I am currently writing a script to get this thing exported out, however if someone already has a solution, please post. Otherwise I will do so after I finish testing it.
Update: I found a workaround to this fairly easily:
% convert a sparse matrix to full
output = full(output);
% output this to a file (excel)
xlswrite('test.csv',output);
I want to know how can this function(from MATLAB) resize the columns of an input image using weights an indices previously computed.
Which equations uses to do that?
resizeColumnsCore(double(in), weights', indices');
When I looked for a function called resizeColumnsCore in MATLAB 7.11.0 (R2010b) I didn't find anything. However, I did find a MEX-file by that name in MATLAB 7.8.0 (R2009a) in this subdirectory of the Image Processing Toolbox:
C:\Program Files\MATLAB\R2009a\toolbox\images\images\private\
I guess they've phased it out or replaced it with another function in newer MATLAB versions. Now, if you want to know what the MEX-file does, you need to look at the source code it is compiled from. Luckily, it appears that this source code resizeColumnsCore.cpp can be found in the following directory:
C:\Program Files\MATLAB\R2009a\toolbox\images\images\private\src\misc\
And you can look through that code to determine the algorithms used to resize the columns of an image given a set of weights and indices.
Now, if you want to know how these input arguments to resizeColumnsCore are computed, you'll have to look at the code of a function that calls it. I know of at least one function in the IPT that calls this function: IMRESIZE. If you type edit imresize at the command prompt it will open that function in the Editor, allowing you to look through the code so you can see how the arguments to resizeColumnsCore are created.
What I can tell you for R2009a is that there is a subfunction in the file imresize.m called contributions which computes the weights and indices that are ultimately passed as arguments to resizeColumnsCore. That is where you will want to start looking to determine what algorithms are used to compute these arguments.
Looks like this isn't a proprietary MATLAB function. Could we see some code or a link to the code?