Pattern matching problem

Hello Community,

I have some video files named using the following pattern:

SHC_LL_S1_0008_V5.5983338494.avi

RHA_RL_S3_0008_v1.59806163.avi

SLR_LL_S1_0008_v1.59806163.avi

I also have some .mat data that corresponds to each video file:

2009-10-15 09-23-54_SHC_RL_S1_0008FinalData

2009-10-15 09-59-31_SLR_RL_S3_0008FinalData

2009-10-15 09-57-11_SLR_RL_S1_0008FinalData

I need to figure out how to load the data files automatically depending on the video selected? I have some experience using the strfind(itemselected,pattern1) function but so far I havent been able to come up with the logic to slove this issue.

Maybe I could store the name of the currently playing video to a variable then try to match that? The key identifiers in the names of both files are:

SHC_LL_S1 SHC_RL_S1

Answer 1

[Fangjun Jiang]

Something like this. BTW, I have to modify your video file name to find a match.

VideoFiles={'SHC_LL_S1_0008_V5.5983338494.avi';
'RHA_RL_S3_0008_v1.59806163.avi';
'SLR_LL_S1_0008_v1.59806163.avi'};

DataFiles={'2009-10-15 09-23-54_SHC_LL_S1_0008FinalData';
'2009-10-15 09-59-31_SLR_RL_S3_0008FinalData';
'2009-10-15 09-57-11_SLR_LL_S1_0008FinalData'};

for k=1:length(VideoFiles)
    Pattern=VideoFiles{k}(1:9);
    Index=strfind(DataFiles,Pattern);
    Index=cellfun(@isempty,Index);
    FoundDataFile=DataFiles(~Index)
end

[B_Richardson]

I see. I'm still getting the hang of looping in matlab. Can you explain some of these lines so I can get the hang of this?

for k=1:length(VideoFiles)

Pattern=VideoFiles{k}(1:9);

Index=strfind(DataFiles,Pattern);

Index=cellfun(@isempty,Index);

FoundDataFile=DataFiles(~Index)

end

[Fangjun Jiang]

The for-loop is to illustrate that you can do this to all your video files. If you only need to find the matching data file for one of your video files, you can do this.

VideoFiles='SHC_LL_S1_0008_V5.5983338494.avi';

DataFiles={'2009-10-15 09-23-54_SHC_LL_S1_0008FinalData';

'2009-10-15 09-59-31_SLR_RL_S3_0008FinalData';

'2009-10-15 09-57-11_SLR_LL_S1_0008FinalData'};

Pattern=VideoFiles(1:9);

Index=strfind(DataFiles,Pattern);

Index=cellfun(@isempty,Index);

FoundDataFile=DataFiles(~Index)

[B_Richardson]

I see. So with this second example I could use the currently selected item in the listbox as VideoFiles, then load all of the filenames into DataFiles{} cell array.

Pattern = VideoFiles; %set pattern

Index=strfind(DataFiles,Pattern); %search through DataFiles

Index=cellfun(@isempty,Index); %get index

FoundDataFile=DataFiles(~Index) %set the found file in FoundDataFile

%Then I can plot(FoundDataFile)

the question I have is will strfind work considering there are files named very similarly? For instance:

SHC_LL_S1_0008_V5.5983338494.avi

SHC_LL_S2_0008_V5.5983338494.avi

SHC_LL_S3_0008_V5.5983338494.avi

SHC_RL_S1_0008_V5.5983338494.avi

SHC_RL_S2_0008_V5.5983338494.avi

SHC_RL_S3_0008_V5.5983338494.avi

So technically the pattern exists to a certain extent in all of these files.

[Fangjun Jiang]

In my code, Pattern is not equal to VideoFiles. It is the first 9 characters of the VideoFiles, such as "SHC_LL_S1". For the video file names you provided, it still produces unique Pattern. As long as the Pattern is unique in your data file names, it will find the right data file. Otherwise, even human can not determine which data file is the right one, right? You then have a different problem to deal with.

[B_Richardson]

Oh so thats what

Pattern=VideoFiles(1:9);

does. it sets the first 9 characters of the VideoFiles in pattern. Very nice.

[B_Richardson]

actually it is

for k=1:length(VideoFiles)

Pattern=VideoFiles{k}(1:9);

that sets the first 9 characters of the VideoFiles in pattern.

Correct?

[B_Richardson]

Do you think this will work?

indexselected = get(handles.listbox1,'Value');

list = get(handles.listbox1,'String');

itemselected = list{indexselected};

%so now itemselected from the listbox is the current movie

files = dir('C:\Users\ecorbett\Documents\VCoachData\0008_Capture_10152009\AccelData') %store entire datafile folder

for i = 1 : numel(files) %loop through folder

for k=1:length(files(i)) %loop through current selected file

Pattern=files{k}(1:9); %set pattern

if strfind(itemselected,Pattern) %test

%do stuff

end

end

[Fangjun Jiang]

You'll have to test it yourself. I apparently don't have all the rest stuff that you have.

[B_Richardson]

Lol, good point. Im sure I can figure out from here. Thank you!!

[Jan]

@Jiang: cellfun('isempty', C) is much faster than cellfun(@isempty, C).

[Fangjun Jiang]

Thanks, Jan. You or somebody else must have reminded me before. I need to stick it into my mind.

Answer 2

[Vairis Caune]

I would suggest an alternative:

VideoFiles={'SHC_LL_S1_0008_V5.5983338494.avi';
'RHA_RL_S3_0008_v1.59806163.avi';
'SLR_LL_S1_0008_v1.59806163.avi'};

for k=1:length(VideoFiles)
    Pattern=VideoFiles{k}(1:14); %take whatever you want
    matfiles=dir(fullfile('C:\placeindisc\folder',['*' Pattern '*']))
        if(length(matfiles)~=1)
            warning('multiple matches or no matches');
        else
            load(matfiles(1).name)
        end
end

If you can have multiple data files per video, then add

for iter=1:length(matfiles)
    load(matfiles(iter).name)
end