In the Matlab function precedence page, it states that function precedence goes:
Functions in the current folder.
Functions elsewhere on the path, in order of appearance.
My question is, when they say "Functions in the current folder" does this exclude functions in subfolders of the current folder? If so, is there a way for me to have subfolders be called preferentially without changing the order of my folders in the path?
I need to do this because I have 2 folders (each with subfolders) of code that run functions with the same name. It seems the subfolders aren't given automatic precedence. I really don't want to have to change my path order every time I run one folder, and I really don't want to have to rename 100s of functions and function calls that my team has written.
The only solution I can think of would be to remove the whole subfolder system and just have a jumbled mess of files in one folder. Are there any other things I can do?
Thanks in advance for the help!
Related
I have a large project coded in MATLAB, with 15-18 scripts. It is becoming very challenging to understand the whole code. I was thinking that if I can put some scripts in another folder, it will become very straightforward to understand and maintain the code. Is it possible to do that?
Consider the below directory structure:
How can I call a function from main.m that is placed in func.m in Folder 1?
Manual solution
Perform the following:
Right click on the folder which is on top of the hierarchy.
click on Add to path
Click on selected folders and subfolders
At this stage, your scripts will be able to identify any function or script which resides in one of the inner subfolders which you chose.
In addition you can call any script and function you would like by simply typing it's name in the command line.
Code solution
Instead of doing it manualy, it is also possible to add folders and subfolders into path by using the following code:
addpath(genpath(<path to your directory>))
Example
The tree structure of the current Matlab path
You can add the functions and scripts from Folder 1 into path by either writing the following code:
addpath(genpath('Folder 1'))
Or by using 'Adding folders and subfolders' option from the menu:
After doing so, it is possible to call func straight from main
I have a folder named "Photos" that is a subfolder of the current directory. Inside that folder, there are four subfolders with names "Order1", "Order2",
"Order3", "Order4". I am trying to open these subfolders using a loop.
The following code is not working.
for i=1:4
current_path=pwd;
cd(current_path');
cd('Photos\Order%d',i);
end
There are a lot issues going on here at the same time.
The primary issue is that you are changing directories each time through the loop but you're also getting the value of the current directory (pwd) each time. The directory doesn't automatically reset to where you were when it goes back to the top of the loop. I think you expect current_path to be the folder you started in and be the same for all iterations.
You need to use sprintf or something similar to create your "OrderN" folder names. cd doesn't know what to do with the format specifier you're trying to use.
You should always use fullfile when concatenating file paths. Period.
You should use absolute paths when possible to remove the dependence upon the current directory.
Do you really need to change the working directory? If you're trying to load files within these folders, please consider using absolute file paths to the files themselves rather than changing folders.
If you are going to do this this way, please be sure to reset the path back to where it was at the end of the loop. There is nothing worse than running code and ending up in a directory that is different than where you were when you called it.
To actually make your code work, we could do something like this. But given all of my points above (specifically, 4-5), I would strongly consider a different approach.
startpath = pwd;
for k = 1:4
folder = fullfile(startpath, 'Photos', sprintf('Order%d', k));
cd(folder)
end
% Set the current directory to what it was before we started
cd(startpath)
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');
My question is how to use MATLAB to search for a certain type of files in a folder. I give an example to detail on my question:
Suppose we have the following folder as well as files in it:
My_folder
Sub_folder1
Sub_sub_folder1
a.txt
1.txt
2.txt
Sub_folder2
3.txt
abc.txt
In this example, I want to find all the .txt files in My_folder as well as its sub-folders. I was wondering what I could do with MATLAB. Thanks!
To my knowledge Matlab doesn't have an inbuilt function to do recursive directory searches, however there are a couple available for download on Matlab Central: here and here.
Alternatively you could write your own recursive function and use the dir function to search at each level for files matching your criterea or other directories to recurse into.
I agree with the Matlab Central options -- another method which I've used when MLC is not an option (no network, or customer computer, etc) is the quick and dirty dos commands:
dos(['dir /s/b ' mywildcard])
The /s will do a recursive directory search for whatever wildcards you specify, and /b will make it so you only get filenames (complete will full path, but no headers, file sizes, etc).
This is obviously platform dependant, so is mostly used when you are forced to work without your "standard" set of utilities you've accumulated.
Even though an answer has been accepted, I would like to point out Matlab's dir function.
This built-in function returns the contents of the folder in question. Furthermore, it indicates which content is a folder of its own. Therefore, with a little loop one could use this function to search sub-directories as well.