how can i open my files?
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hi everybody today i have one question too!! i use fopen function to open my Experiment datas. but the Name and Extension of files vary from each other. could you give me informations have can i read all files automatically.Inaddtion beginning of files Name differs from each other too. example: msa02_141121_mscc5_11.erg m4_cst_cc3_150206_01.e00 and here is my code too in order to read first file. As you can guess i have maybe more than 1000 files so i want to read them in Loop..
clear all
clc
delimiter=';' ;
headerLines=4
formatSpec1 = '%s%s%s%s%s%[^\n\r]'
daten=fopen('msa02_141121_mscc5_11.erg','r')
zeile = textscan(daten,formatSpec1,181,'delimiter',';','headerLines',4)
fclose(daten);
Accepted Answer
Image Analyst
on 13 Feb 2015
0 votes
Use dir(), or sprintf() depending on what you know or don't know and how you want to do it. Code samples are in the FAQ: http://matlab.wikia.com/wiki/FAQ#How_can_I_process_a_sequence_of_files.3F
39 Comments
cemsi888
on 13 Feb 2015
Stephen23
on 13 Feb 2015
Then use the dir option, as Image Analyst suggested and as the Wiki also explains.
You don't show us how you are calling these functions, so it is hard to know what is happening. But there are a few points to pay attention to:
- Why are there two callback functions? If you have one callback event, then the variables in one function workspace are not going to magically jump into the other workspace, so why do you separate them? For example there is no way for name to jump magically from loaddata_Callback to Read_Callback.
- You do nothing inside the first for loop anyway, apart from assign one name value to C, which then never gets used. What is the point of that?
- Calling fopen('C','r') will try to open a file named 'C' in the current directory. If you want to refer to the variable C, then you need to remove those single-quotes so that it is a variable and not a string.
- Do not use path as a variable name, as path is already defined in MATLAB.
- You should use fullfile rather than simply concatenating the path and filenames.
- Why are the uigetfile file-types labeled as being 'All Matlab Files'? Those are not standard MATLAB file extensions.
- Learn to use the semicolon to suppress displaying outputs.
Something like this should work:
function loadData_Callback(hObject, eventdata, handles)
%
[N_cell,P_str] = uigetfile({'*.erg';'*.e00'},'A better description','Multiselect','on');
%
for k = 1:numel(N_cell)*~isequal(0,P_str)
temp = fullfile(P_str,N_cell{k});
fid = fopen(temp,'r');
zeile = textscan(fid,...)
fclose(fid);
end
The code is currently unreadble: please learn to format your code correctly on this forum. You can use the {} Code button above the textbox, and review it using the preview panel below the textbox.
The code actually does something different to what you described: loadData_Callback does not open any files (or even load them), but merely generates some filepath strings, whereas Read_Callback really does open and read the data files, using fopen and textscan. It should close them too.
cemsi888
on 16 Feb 2015
cemsi888
on 16 Feb 2015
Image Analyst
on 16 Feb 2015
Are you still having trouble or not? If so, please attach all files necessary for us to run the code with the paper clip icon.
cemsi888
on 16 Feb 2015
cemsi888
on 16 Feb 2015
Image Analyst
on 16 Feb 2015
Your loaddata callback gets the filename but then it's lost as the function exits. You don't do anything with it. In the other callback you don't use the filename but instead use some undefined variable called C. Why??? Just make the filename global or attach it as a field to the handles structure and use that in fopen().
Stephen23
on 16 Feb 2015
If you want to keep the filepath generation and file-reading in separate functions, then you will need a way to transfer that filepath information from one callback function to the other. I would suggest using guidata for this. Something a bit like this:
function makeFilename_Callback(hObject, eventdata, handles)
%
[A.path,A.names] = uigetfile({'*.erg';'*.e00'},'description...','Multiselect','on');
guidata(hObject,A);
end
function Read_Callback(hObject, eventdata, handles)
%
A = guidata(hObject);
if isempty(A)||~isstruct(A)
return
end
for k = 1:numel(A.names)
temp = fullfile(A.path,A.names{k});
fid = fopen(temp,'r');
zeile = textscan(fid,...)
fclose(fid);
end
end
cemsi888
on 17 Feb 2015
cemsi888
on 17 Feb 2015
cemsi888
on 17 Feb 2015
Some hints to make your own life easier:
- pay attention to the MATLAB Editor's code warnings. Currently I get a whole pile of orange warnings about small improvements that could be made.
- format your code consistently. Currently your indenting is quite random: use the standard four space characters for loops and the like. This will make it easier to notice problems like not having enough end's.
- Learn to use the MATLAB debugging tools. An important part of writing code is knowing how to debug code. Learning to debug makes you much more independent, a better programmer and teaches you new things about the language you are using.
- Use MATLAB's documentation. Don't just copy the code that someone puts here in an answer. Read about the functions and operations that it uses, and understand how it works.
Image Analyst
on 17 Feb 2015
Attach the fig file also, otherwise we can't run your program.
cemsi888
on 17 Feb 2015
cemsi888
on 17 Feb 2015
Stephen23
on 17 Feb 2015
cemsi888
on 17 Feb 2015
Image Analyst
on 17 Feb 2015
Just put
global yourVariable;
in whatever function that needs to use yourVariable. Functions that don't have that won't be able to see yourVariable, and functions that do have that will be able to see it.
cemsi888
on 18 Feb 2015
Stephen23
on 18 Feb 2015
It is possible to do this, but if you only want to view them in order to check if your code is working properly then use the MATLAB debugging tools rather than assignin.
cemsi888
on 18 Feb 2015
This is probably because your files are located in a different directory to your current working directory, and so if you only supply fopen with the filename it looks in the current directory and cannot find a file with that name.
The solution to this is to also obtain the second output of uigetfile (the filepath), join this onto the filenames (use fullpath to do this, do not use string concatenation), and then pass this full filepath to fopen.
Here is one way to use fullpath with a cell array of filenames:
>> fnm = {'Anna.txt','Bob.txt','Cath.txt'};
>> pth = 'C:\foo\bar';
>> fpt = cellfun(@(s)fullfile(pth,s), fnm, 'UniformOutput',false);
Optionally you could include some handling for the case of if the users deletes the dialog box, or does not select any files.
cemsi888
on 23 Feb 2015
cemsi888
on 23 Feb 2015
You should probably end your functions. Defining functions without end can be a bit ambiguous where they end.
Every time that you call
assignin('base','zeile',zeile)
it replaces any data that already exists in your workspace with the name zeile with the some new data with the same name. If you want to see all of the data, then you need to change the name each time.
Actually I would recommend that you avoid using assignin completely, and learn to use the debugger to check variables.
Note that creating lots of variables with dynamic names is a really bad idea. In case you are interested, here are some pages explaining why dynamically assigning variable names is a really bad idea in MATLAB:
"if i did not use assigin i can not see zeile on Workspace": correct, and this is exactly the point. By choosing to use assignin you are making your own life more difficult, as doing this requires dynamic names and writes over existing variables. Bad idea. You should not be using assignin to move variables around between workspaces. Consider instead:
- Use the debugging tools to view a function workspace.
- Use output arguments to return values from a function to the base workspace.
Each function (and base) has its own workspace. What happens inside a function should be invisible to the outside world: the algorithm is irrelevant, the only thing that matters is the output argument. The only time it should be necessary to look at a function's workspace is when it is being written or debugged, in which case the debugger is the best tool for this job. If you need to move data from a function workspace to another workspace, use the output arguments of the function itself. Learn to avoid assignin, and your code will become better, neater and more reliable.
cemsi888
on 24 Feb 2015
cemsi888
on 24 Feb 2015
cemsi888
on 24 Feb 2015
Image Analyst
on 24 Feb 2015
It needs to send back a cell array when there's a list of strings because all the strings may not be the same size. If there's just one I'd guess it's a string because that's a lot simpler and no cell array is required.
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