Extract information from path name - matlab

Question

I want to make a script in MATLAB that saves my output data with a certain name. All information for this name is in the path from the input data, like it is shown here:
path = 'C:\projektions100\algorithm1\method_A\data1';
projection =
algorithm =
method =
data =
The script then should extract the text in the path with the keyword (f.e. method) from the adjacent backslashes so the script is more flexible in case I made a spelling mistake with some folder names.
This is what I found to extract a text between a start and a end point but I cannot simply use the backslashes since there are a few of them in the path.
How should I proceed?

Answer 1

You can simply use a regexp with named tokens:
>> path = 'C:\projektions100\algorithm1\method_A\data1';
>> all=regexp(path,'[^\\]+\\proje[ck]tion(?<projection>[^\\]+)\\algorithm(?<algorithm>[^\\]+)\\method(?<method>[^\\]+)\\data(?<data>.+$)','names')
all =
struct with fields:
projection: 's100'
algorithm: '1'
method: '_A'
data: '1'

Answer 2

The problem is on how to find the end of your keywords. Here is a bit code, which loops through the keywords and looks for them in the path (stored in p2fldr, because the variable path returns the working path in MATLAB and you overshadow it if you define it).
p2fldr = 'C:\projektions100\algorithm1\method_A\data1';
% keywords
kyWrd = {'projection','algorithm','method','data'};
Tag = cell(size(kyWrd));
for i = 1:length(kyWrd)
% get keyword
ky = kyWrd{i};
% look for it in the path
idx = strfind(p2fldr,ky);
if ~isempty(idx)
% remaining path
idx_offset = idx+strlength(ky);
prm = p2fldr(idx_offset:end);
% look for file separator '\'
idx_tmp = strfind(prm,filesep);
% if you don't find one, it is pabably the last entry, so take the
% length
if isempty(idx_tmp)
idx_tmp = length(prm)+1;
end
% this is the index where it ends
idx2 = idx_tmp(1)-1;
% assign to tag-cell
Tag{i} = prm(1:idx2);
end
end
You can build a shortcut if you know that they are always in the last 4 entries of your path, so you can use strsplit right away and index the last returned cells
str_splt = strsplit(p2fldr,filesep);
Tag = cell(size(kyWrd));
for i = 1:length(kyWrd)
% index cells
str = str_splt{end-length(kyWrd)+i};
% get keyword
ky = kyWrd{i};
Tag{i} = str(length(ky)+1:end);
end
Note that this does not care if it matches your keywords (e.g. your path says 'projektions' but I defined the keyword to be 'projection')