Cut and re-join strings

Hello, I am trying to create a function that will cut a section out of a string and join the two remaining parts togather.

I am getting some weird results towards the end

here is my code

pat = 'MATLAB';
cliplength = length(pat);
stringinput = 'D:\Documents and Settings\212068586\My Documents\MATLAB\help'

endpoint = regexp(stringinput, pat);
newstringstart = [];
newstringtail = [];
for w = 1:length(stringinput) 
    if w < endpoint
        newstringstart(w) = stringinput(w);
    end

end
    if (((endpoint + cliplength) < w) && (w > endpoint)) 
        for h = (endpoint + cliplength):length(stringinput) 
            newstringtail(h) = stringinput(w);
        end

          %newstring(w) = stringinput(w - (endpoint + cliplength));
      end

disp(char(strcat(newstringstart, newstringtail)))

Any ideas why it isn't working?

Thanks

Bill

Answer 1

[Matt Fig]

Rather than using a verbal description, show us what you want. For example, if you start with these:

pat = 'MATLAB';
stringinput = 'D:\Documents and Settings\212068586\My Documents\MATLAB\help'

what do you want to have at the end?

[William]

Basically I would like to cut the '\MATLAB' out and slide the two remaining parts togather.

Thanks

[Matt Fig]

Ah, now that was easy!

regexprep(stringinput,'\MATLAB','')

[Matt Fig]

See also the help for STRREP, which would do the same thing.

strrep(stringinput,'\MATLAB','')

[Walter Roberson]

Agggh, the quote-eater got me!

strrep(stringinput,'\MATLAB\,'\')

instead of what Matt and Fangjun Jiang suggested. Otherwise if your username was MATLABUSER your output would become 'D:\Documents and Settings\USER\My Documents\MATLAB\help' instead of your desired 'D:\Documents and Settings\MATLABUSER\My Documents\help'

[Matt Fig]

Good catch, Walter. Now lets hope that there aren't two directories named MATLAB...

strrep(stringinput,'\MATLAB\','\')

If there are two directories named MATLAB, you could use FINDSTR to find their indices, then replace whichever one you want using the appropriate index into the original. For example:

stringinput = 'D:\Documents and Settings\MATLAB\My Documents\MATLAB\help'

I = findstr(stringinput,'\MATLAB\')

stringinput(I(2):I(2)+6) = []

[Fangjun Jiang]

Guys, you seem to have too much fun. What about my advise on using path related functions.

[Matt Fig]

Fangjun, that would be fine, but I was going for something more general - string manipulation.

[Fangjun Jiang]

That is my point. William has been asking about a few string manipulation questions but his example always show file path. That is why I asked him about his overall task.

[Walter Roberson]

fileparts() was recommended to William in a previous question but he chose to go with his much more complex and non-obvious code.

On the other hand, perhaps now that he sees how messy it can be to do such things properly with string manipulation, he will reconsider using fileparts()

Speaking of messiness: did anyone mention that in modern MS Windows, '/' is just as valid a path separator as '\' is, and that one should thus be prepared for the possibility that one might be dealing with (for example) 'D:\Documents and Settings\31415926\My Documents/MATLAB/help' ...

[Fangjun Jiang]

I did not know that but apparently it is, both in MATLAB and Windows Explorer. Is it good or bad?

[Matt Fig]

I just tried it in Windows 7 and you are correct in at least one sense. I pasted:

C:/Users/matt fig/Desktop/General

into the location bar of an open folder and was taken to the correct location. However, the OS immediately changed the location to:

C:\Users\matt fig\Desktop\General

So I wonder if an inquiry from MATLAB would ever really return a string with / in it?

[Walter Roberson]

Yes, some inquiries from MATLAB return or directory names as passed in to MATLAB rather than canonicalizing the paths.

I do not know if cd() or uigetdir() on Windows could ever be convinced to return a \ delimited name. Possibly so, see the last paragraph or so of the below-referenced blog.

This state of accepting / or \ has been part of Windows from the beginning: it dates right back to the introduction of directories in DOS. See the following blog from a Microsoft Employee: http://blogs.msdn.com/b/larryosterman/archive/2005/06/24/432386.aspx

Answer 2

[Fangjun Jiang]

Bill, What type of task are you dealing with? I suggest you changing your mind set a little bit. Based on the description part of your question, would this solve your problem? Try not to think of the string at one letter a time.

strrep(stringinput,'MATLAB','')

[William]

I am dealing with strings that are file locations c\: ..... place.... and need to cut and paste some strings to look in subfolders and directories. I have been tasked with trying to continue on where a very talented MATLAB programmer left off and have been pretty frusterated.

The script I wrote is for a function I am writing to try and figure out how to cut and paste strings togather. Thank you for all your help

Bill

[Fangjun Jiang]

If you need to deal with the full path of a file or directory, then using related function makes more sense then processing it as ordinary string. Use the following functions:

[PathStr]=fileparts(stringinput)

and you repeat it again and again

fileparts(PathStr)

Other functions are:

fullfile()

exist(PathStr,'file')

exist(PathStr,'dir')

which(Path)

pwd

cd