Get full path of directory that is on Matlab search path

Hello,

I have a folder called 'mydir' that is in the Matlab search path but not in my current directory. Thus isdir('mydir') is true. Is there a way to easily extract the full path of 'mydir' in this scenario?

Thanks, Justin

Answer 1

[per isakson]

One way

>> s = what('InUse');
>> s.path
ans =
h:\m\FEX\InUse

where InUse is a folder on my Matlab path

[Walter Roberson]

Interesting answer.

You need {s.path} though as there can be multiple results.

I notice that this will find directories in which the name appears as the name of a package. For example if you what('matlab') then one of the directories found would be (for example) '/Applications/MATLAB_R2017a.app/toolbox/distcomp/bigdata/+matlab' in which 'matlab' does not exist as a literal directory name. isdir('+matlab') says 0

Locating packages might be useful.

[per isakson]

Yes that right. Doc says: " You do not need to specify the @ or + symbol for class and package folders."

[Justin Solomon]

Thanks! This works for my situation!

Answer 2

[Walter Roberson]

Easy? Ummm, how about possible in a few lines?

tofind = 'mydir';

esctofind = regexptranslate('escape', tofind);   %in case it has special characters

dirs = regexp(path, pathsep,'split');          %cell of all individual paths
temp = unique(cellfun(@(P) strjoin(P(1:find(strcmp(esctofind, P),1,'last')),filesep), regexp(dirs,filesep,'split'), 'uniform', 0));    %don't let the blue smoke escape
fullpaths = temp(~cellfun(@isempty,temp));     %non-empty results only

Notes:

1. fullpaths will be a cell array of character vectors
2. fullpaths might have multiple entries, as there might be multiple matches
3. it is possible for any one path to have multiple occurrences of the same directory name; this code deliberately goes for the longest version. For example if the search was for 'matlab' then it would pick /Applications/MATLAB_R2017a.app/toolbox/matlab/datatools/inspector/matlab instead of /Applications/MATLAB_R2017a.app/toolbox/matlab
4. the directory name to find may have special characters such as '.' which will be treated literally, not as wild-cards
5. the code as posted will not match package directories that have '+' or '@' before the name being searched for, but that would be easy to add. The code will find such directories if you ask for them specifically.
6. the code has been designed to work on Windows, Mac, and Linux

[Justin Solomon]

Thanks Walter, this is is great solution and seems to be robust against many situations.