Suppose two different Matlab users share a computer and they each want to be able to save and load their own Matlab paths. (Or, a single user wants to use different paths at different times.) What's the easiest way to handle this?
Should there be multiple pathdef files? Alternatively, should they each have a script that calls restoredefaultpath and then uses addpath to add new paths?
You can use the startup.m file for that.
When starting up, Matlab executes the file matlabrc.m, which is the master startup file, and is common for all users. Among other things, this file
Sets the first entry of the path as the user-folder of the current user, that is, the user that started Matlab. (This is done by calling pathdef, which in turn calls userpath); and then
Looks for a startup.m file in the path, end executes if it exists.
Therefore you can place a user-specific startup.m file in each user's folder, and Matlab will run the appropriate file depending on which user started Matlab. In that file you can set the path on a per-user basis, and do other user-related stuff.
Related
Where can i save my document "function.m", so i can call this function from any code in any path of my pc?
I already made some custom functions, but i dont know where to save those codes to be able to call them from any part.
Save them in a logical place where you can find them back. Then, use addpath to add that folder to MATLAB's search path, i.e. when you use a function it will try that folder as well to find it.
You can do this either per script, or edit startup.m with this, so that it's automatically included when MATLAB starts.
Alternatively to Adriaan's best practice answer, the fastest option is to save your function.m in the %USERPROFILE%/Documents/MATLAB directory on your PC ($home/Documents/MATLAB on Linux and Mac). This directory is on your MATLAB Search Path by default. This might be an acceptable solution if you use the function commonly across different projects.
Finally, there is a "manual" solution: Execute pathtool in MATLAB, add the directory containing your function.m via the GUI and hit save.
My team is trying to standardise our Matlab paths so that everyone has the same.
I have a list of the default matlab path that we should all have.
So we would like to have a script that runs when matlab opens to make sure that our paths are set to the default matlab path. So if a path has been added to our default list it will be added in the correct place.
Is this possible in Matlab?
I read about startup but that seems to do with set your working directory which is different to what I am trying to do.
You can change which directory MATLAB starts in using the userpath function so that whenever you start up MATLAB, the path will automatically redirect here.
This may be useful if you have MATLAB running on a network per se, and multiple instances can start in the same network directory.
See more from MathWorks here: http://www.mathworks.com/help/matlab/matlab_env/matlab-startup-folder.html
However, if you want to standardize everything so that everyone has access to the same path, you can use startup to add directories / folders to MATLAB's path, but if you want to complete the package, use userpath to get MATLAB to start at a specified directory.
Your startup.m file may look something like this:
addpath('/folder/to/add/one');
addpath('/folder/to/add/two');
addpath('/folder/to/add/three');
addpath('/folder/to/add/four');
Then set your userpath with the function to complete everything:
userpath('/folder/to/start');
addpath('/folder/to/start');
Also make sure you add this new folder to your startup.m file too.
Include a path or addpath line in file startup.m. For example, to add folder aaa\bbb to the path the line would be
addpath('aaa\bbb')
Note that each user may have a different startup.m file. You may need to create it, if it doesn't already exist.
I have created a few general function in MATLAB that I intend to use for a few separate projects. However I do not want to copy the function into each separate project function.
I have created a folder called Misc_Function when I have placed these general functions. I know I can reference this functions explicitly by using the path and function name when trying to call the functions.
I believe you can add a path (in my case 'H:\MyTeam\Matlab\Misc_Function') when MATLAB loads up is that correct and if so how do you do this?
Assuming the above can be done I'm interested to know how MATLAB finds the correct function. In my understanding (guess work) MATLAB has a list of paths that it check trying to find a function with the name specified - is that correct? If so what happens when there are functions with the same name?
MATLAB indeed has its own search path which is a collection of folders that MATLAB will search when you reference a function or class (and a few other things). To see the search path, type path at the MATLAB prompt. From the documentation:
The order of folders on the search path is important. When files with the same name appear in multiple folders on the search path, MATLAB uses the one found in the folder nearest to the top of the search path.
If you have a set of utility functions that you want to make available to your projects, add the folder to the top of the search path with the addpath function, like so
addpath('H:\MyTeam\Matlab\Misc_Function');
You have to do this everytime you start MATLAB. Alternatively, and more conveniently, save the current search path with the savepath command or add the above commands to your startup.m file.
You can check the actual paths where Matlab searches for functions using
path
You will notice, that the most top path (on start up) is a path in your home folder. For Linux this is e.g. /home/$USER/Documents/MATLAB. For Windows it is somewhere in the the c:\Users\%USER%\Documents\Matlab (I think). Placing a file startup.m in this folder allows to add additional paths using
addpath('H:\MyTeam\Matlab\Misc_Function');
or
addpath(genpath('H:\MyTeam\Matlab\Misc_Function'));
on start up of Matlab. The latter (genpath) allows to also add all subdirectories. Simply write a file startup.m and add one of above lines there.
I believe 'addpath' will add the folder to MATLAB path only for the current MATLAB session. To save the updated path for other sessions, you need to execute 'savepath' command.
As mentioned in the previous comments, adding the folder in startup.m is a good idea since it will be added to the path on MATLAB startup.
To answer your question about how MATLAB finds the correct function, MATLAB maintains a list of directories in its path in a file called pathdef.m. Any changes to the path will be written to this file (when you execute 'savepath'). The path variable is initialized with the contents of this file.
I have been working on MATLAB scripts.
Basically, I have a lot of functions and data files (collectively known as kernels):
I want to organize it a little bit.
The idea is
to create a subfolder named functions and save all functions in it.
Another kernels and save all data kernel files in it.
Later by adding these paths at runtime, all the scripts should be able to access these functions and kernels without giving the full path to them, i.e. The script should search it in the subfodlers too.
Applying addpath(genpath(pwd)); worked for functions but it couldn't access kernel files
e.g. What if I want to access file named naif0010.tls inside subfolder kernels.
It didn't work. Any suggestions.
Example:
% Add the current script directory and subfolders to search path
addpath(genpath(pwd));
% Load NASA Spice (mice) to the script here
% add MICE reference path to MATLAB
addpath('C:\Program Files\MATLAB\R2012b\extern\mice\src\mice');
addpath('C:\Program Files\MATLAB\R2012b\extern\mice\lib');
% Load leap second kernel
% If the leapsecond kernel is placed in script directory
% This file is present in pwd/kernel/naif0010.tls
cspice_furnsh('naif0010.tls');
There are a couple of things to keep in mind. First, your current working directory (pwd) is in the Matlab path by default, so you don't usually need to explicitly call addpath in order to use scripts, functions, or data files there.
Also, in many cases you can access files by providing a relative path rather than an absolute path. In your case, this would look like
cspice_furnsh('kernels/naif0010.tls')
I solved it with some work around which I know is not the correct answer but for now I can go ahead....
addpath(genpath(pwd));
% Basically just forming full path of the data file
leapSecondsFile = fullfile(pwd,'kernels','naif0010.tls');
cspice_furnsh(leapSecondsFile);
Still waiting for correct answer or suggestions :-)
Update:
Thanks nispio's comment above, The correct way is :
% Load current directory and subfolders
addpath(genpath(pwd)); % This is not necessary
cspice_furnsh('kernels\naif0010.tls');
Today I stumbled upon this thread:
http://www.mathworks.com/matlabcentral/newsreader/view_thread/112560
The question is basically how to make Matlab read your startup.m file regardless of where
you start your matlab session.
One of the solutions offered was:
One solution would be to ask the system administrator to add a few lines
to "matlabrc.m" that adds some pre-determined folder in the user's home
directory to the MATLAB path (say, ~/.matlabstart). Then each user can
have their own "startup.m" file inside this folder.
What I ended up doing in my system (OS X) was to add a startup.m file in:
/Applications/MATLAB_R2011a.app/toolbox/local/
In this startup.m file I added:
if exist([getenv('HOME') '/.matlabrc/startup.m'])
run([getenv('HOME') '/.matlabrc/startup.m']);
end
That way users have the option of creating the hidden folder ~/.matlabrc and inside it they can put the file startup.m. In this startup file they can tell matlab what to execute whenever they start Matlab regardless of the directory where they started it. An example of what I added to my own personal startup.m file is
addpath(genpath('/Users/jmlopez/matlabcode/'))
Now I can add as many folders inside that directory and all of them will be added
to the path every time I start Matlab automatically without having to modify the path.
The question is: Did Matlab already provided a special file like the one I created or did I just go through all this trouble to accomplish what I wanted? If the answer is the second option I gave, then, why doesn't Matlab provide this? It is such a pain in the ass to add directories to the Matlab path whenever you do not have admin permissions and I do not want to carry my startup.m file to every directory I go to. Can someone shed some light into this please?
You can save the pathdef file (which stores all the paths you add) to a custom directory. The problem however is that when matlab starts, it doesn't automatically know which custom directory you used in the previous session.
But that's where the MATLABPATH environment variable comes in. Because this allows to set the matlab starting path yourself. In linux this is simply done by setting this environment variable MATLABPATH before starting matlab (from a terminal / in your .bashrc / ...)
export MATLABPATH=$HOME/.matlab
This way you can let all users have their own pathdef file, which solves the problem of having to add them manually at startup.
EDIT
I tested out if adding startup.m to that MATLABPATH directory worked, ie: does matlab run that startup file? ... and it does. I think it doesn't work for you, because there is another startup.m file in some other (higher priority) directory (probably matlabroot), so that gets precedence. My only startup file is in MATLABPATH, so there is only one choice.
EDIT2
Nope, I added startup to matlabroot directory, and still my own startup file in .matlab gets run. Are you sure you set the MATLABPATH correctly before you started matlab?