I have an application that translates the .csv files I currently have into the correct format I need. But, the files I that I do have seem to have '"' double quotes around them, as seen in this image, which will not work with the program. As a result, I'm using this command to remove them:
for m = 1:currentsize(1)
for n = 1:currentsize(2)
replacement{m,n} = strrep(current{m,n}, '"', '');
end
end
I'm not entirely sure that this works though, as it spits this back at me as it runs:
Warning: Inputs must be character arrays or cell arrays of strings.
When I open the file in matlab, it seems to only have the single quotes around it, which is normal for any other file. However, when I open it in notepad++, it seems to have '"' double quotes around everything. Is there a way to remove these double quotes in any other way? My code doesn't seem to do anything as seen here:
After using xlswrite to write the replacement cell-array to a .csv file, one appears corrupted. Any idea why?
So, my questions are:
Is there any way to remove the quotes in a more efficient manner or without rewriting to a csv?
and
What exactly is causing the corruption in the xlswrite function? The variable replacement seems perfectly normal.
Thanks in advance!
Regarding the "corrupted" file. That's not a corrupted file, that's an xls file (not xlsx). You could verify this opening the text file in a hex editor to compare the signature. This happens when you chose no file extension or ask excel to write a file which can't be encoded into csv. I assume it's some character which causes the problems, try to isolate the critical line writing only parts of the cell.
Regarding your warning, not having the actual input I could only guess what's wrong. Again, I can only give some advices to debug the problem yourself. Run this code:
lastwarn('')
for m = 1:currentsize(1)
for n = 1:currentsize(2)
replacement{m,n} = strrep(current{m,n}, '"', '');
if ~isempty(lastwarn)
keyboard
lastwarn('')
end
end
end
This will launch the debugger when a warning is raised, allowing you to check the content of current{m,n}
It is mentionned in the documentation of strrep that :
The strrep function does not find empty strings for replacement. That is, when origStr and oldSubstr both contain the empty string (''), strrep does not replace '' with the contents of newSubstr.
You can use this user function substr like this :
for m = 1:currentsize(1)
for n = 1:currentsize(2)
replacement{m,n} = substr(current{m,n}, 2, -1);
end
end
Please use xlswrite function like this :
[status,message] = xlswrite(___)
and check the status if it is zero, that means the function did not succeed and an error message is generated in message as string.
Related
Basically, I build a list of files using ls, then want to loop through that list, read in a file, and do some stuff. But when I try to read the file in it fails.
Here is an example
r=ls(['Event_2006_334_21_20_11' '/*.r'])
Event_2006_334_21_20_11/IU.OTAV_1.0.i.r
which is a 1x80 char
fopen(r(1,:))
-1
but
fopen('Event_2006_334_21_20_11/IU.OTAV_1.0.i.r')
12 (or whatever its on)
works. I've tried string(r) and char(r) and sprintf('%s',r). If I just build the string like r = ['Event_2006_334_21_20_11' '/IU.OTAV_1.0.i.r'] it works. So it seems something about combining the different variable types that messes it up but I can't seem to find a workaround. Probably something obvious I'm missing.
Any suggestions?
ls returns a matrix of characters, which means each row contains the same number of characters. To indicate the problem, try:
['-' r(1,:) '-']
You will probably notice some whitespaces in front of the -. Unless you want to print the output to the command line, ls is not really useful. As mentioned by Alex, use dir instead.
A further tip regarding your last comment, concatenate file path using fullfile. It makes sure you get one file separator whenever concatenating:
>> fullfile('myfolder','mysubfolder','myfile.m')
ans = myfolder/mysubfolder/myfile.m
>> fullfile('myfolder/','mysubfolder','myfile.m')
ans = myfolder/mysubfolder/myfile.m
>> fullfile('myfolder/','/mysubfolder','myfile.m')
ans = myfolder/mysubfolder/myfile.m
Is it possible to use checkcode or matlab.internal.codeanalyzer to parse a string of code, for example:
for i=1:100 a*b(i); end
without first putting that in a file and then calling checkcode or the internal parser.parse on that file. I want to check thousands of strings of code but dynamically without putting them in a file before each check. Ideally, I would like to be able to parse a string with the code in and have that parsed.
To be more clear incase there are other functions that could be useful, I actually want to parse a string and count the number of syntax errors, and find their location etc.
Seems mlintmex has a -text option which one can use to pass a string. It needs a string and a filename, however, it seems not to even use the filename, so not sure why. Furthermore, I can't figure out why, but when using -text there needs to be at least one parseable command. Therefore instead of calling
fid = fopen('tmp.m','wt');
fprintf(fid, '-mean[1:10)');
fclose(fid);
info = checkcode('tmp.m', '-fullpath');
one can use the following which has a great increase in performance:
% Get the errors with text mode
info = checkcode(['1;','-mean[1:10)'], 'tmp.m', '-fullpath', '-text');
% Reduce the columns to take in to account the '1;' in the checkcode call above.
for i=1:numel(info)
info(i).column = info(i).column - 2;
end
Using tic and toc in a loop for 1000 times, I get ~9 seconds for the file version and ~3-4 seconds for the -text version.
I'm trying to export a matrix f that is double. My data in f are real numbers in three columns. I want a txt file as an output with the columns separated by tabs. However, when I try the dlmwrite function, just the first column appears as output.
for k = 1:10
f = [idx', firsttime', sectime'];
filename = strcat(('/User/Detection_rerun/AF_TIMIT/1_state/mergedlabels_train/'),(files_train{k,1}),'.lab');
dlmwrite(filename,f,'\t') ;
end
When I use dlmwrite(filename,f,'\t','newline','pc') ; I keep getting an error Invalid attribute tag: \t . I even tried 'tab' instead of '\t' but a similar error appears. Please let me know if you have any suggestions. thank you
This is because you are not calling dlmwrite properly. To specify the delimiter, you must use the delimiter flag, followed by the specific delimiter you want. In your case, you use \t. In other words, you need to do this:
for k = 1:10
f = [idx', firsttime', sectime'];
filename = strcat(('/User/Detection_rerun/AF_TIMIT/1_state/mergedlabels_train/'),(files_train{k,1}),'.lab');
dlmwrite(filename,f,'delimiter','\t') ;
end
BTW, you are using the newline flag with pc, meaning that you are specifying carriage returns that are recognized by a PC. I suggest you leave this out and allow MATLAB to automatically infer this. Only force the newline characters if you know what you're doing.
FWIW, the MATLAB documentation is pretty clear about delimiters and other quirks about the function: http://www.mathworks.com/help/matlab/ref/dlmwrite.html
I am writing a program to plot graphs in a loop and I want to save each graph that comes out as a .jpg file with a variation of the file name. Here is my code for saving the graphs:
filename = strcat('WI_Pollutants_', D(i,6), '_200706_O3');
saveas(gcf, filename, 'jpg');
The saved file should come out as the following with D(i,6) changing each iteration of the loop.
WI_Pollutants_003-0010_200706_O3.jpg
However, I'm running an error: (Maybe it has to due with saveas wanting a string only?)
Error using saveas (line 81)
Invalid filename.
saveas only accepts characters as the filename. But when filename was created, strcat made it a cell array. Therefore, the filename needs to be converted to a character array.
filename = char(strcat('WI_Pollutants_', D(i,6), '_200706_O3'));
saveas(gcf, filename, 'jpg');
This solves the problem.
I think your D{i,6} is ending up wrapped up as an array, from this line:
D{i,6} = [num2str(D{i,6}) '-' num2str(D{i,7})];
To solve this, just removing the []'s
D{i,6} = num2str(D{i,6}) '-' num2str(D{i,7});
I think what happened is your D{i,6}=['someString'], and concatinating added in the []'s that werent' desired.
As a check, if something like this happens again, just fprintf(filename) right before use, and look at what comes out. I suspect you'll find the issue there. You can always remove the print statement later on.
I have a file full of ascii data. How would I append a string to the first line of the file? I cannot find that sort of functionality using fopen (it seems to only append at the end and nothing else.)
The following is a pure MATLAB solution:
% write first line
dlmwrite('output.txt', 'string 1st line', 'delimiter', '')
% append rest of file
dlmwrite('output.txt', fileread('input.txt'), '-append', 'delimiter', '')
% overwrite on original file
movefile('output.txt', 'input.txt')
Option 1:
I would suggest calling some system commands from within MATLAB. One possibility on Windows is to write your new line of text to its own file and then use the DOS for command to concatenate the two files. Here's what the call would look like in MATLAB:
!for %f in ("file1.txt", "file2.txt") do type "%f" >> "new.txt"
I used the ! (bang) operator to invoke the command from within MATLAB. The command above sequentially pipes the contents of "file1.txt" and "file2.txt" to the file "new.txt". Keep in mind that you will probably have to end the first file with a new line character to get things to append correctly.
Another alternative to the above command would be:
!for %f in ("file2.txt") do type "%f" >> "file1.txt"
which appends the contents of "file2.txt" to "file1.txt", resulting in "file1.txt" containing the concatenated text instead of creating a new file.
If you have your file names in strings, you can create the command as a string and use the SYSTEM command instead of the ! operator. For example:
a = 'file1.txt';
b = 'file2.txt';
system(['for %f in ("' b '") do type "%f" >> "' a '"']);
Option 2:
One MATLAB only solution, in addition to Amro's, is:
dlmwrite('file.txt',['first line' 13 10 fileread('file.txt')],'delimiter','');
This uses FILEREAD to read the text file contents into a string, concatenates the new line you want to add (along with the ASCII codes for a carriage return and a line feed/new line), then overwrites the original file using DLMWRITE.
I get the feeling Option #1 might perform faster than this pure MATLAB solution for huge text files, but I don't know that for sure. ;)
How about using the frewind(fid) function to take the pointer to the beginning of the file?
I had a similar requirement and tried frewind() followed by the necessary fprintf() statement.
But, warning: It will overwrite on whichever is the 1st line. Since in my case, I was the one writing the file, I put a dummy data at the starting of the file and then at the end, let that be overwritten after the operations specified above.
BTW, even I am facing one problem with this solution, that, depending on the length(/size) of the dummy data and actual data, the program either leaves part of the dummy data on the same line, or bring my new data to the 2nd line..
Any tip in this regards is highly appreciated.