Could anyone explain the code for me ?

file_path = dir(''); fid = fopen(''); pattern_col = 0;

while ~feof(fid)

    pattern_col = pattern_col + 1;  %coloum increment is 1
    exp = [];               %initialize the sample data
    area_sample = [];
    angle_sample = [];
    fcontent = fgetl(fid);  %get pattern size
    pattern_size = fcontent;
    fcontent = fgetl(fid);  %get time interval
    pattern_hour = fcontent;
    fcontent = fgetl(fid);  %get file path
    file_path_disp = fcontent;
    file_path = dir(fcontent);      %should be specific
    file_num = size(file_path, 1);

Could anyone explain the code for me ? It can read a image file ? especially the beginning. file_path = dir(''); fid = fopen('');

Can you make up some example for me ? thanks

[Michael Haderlein]

This code looks incomplete. The first line doesn't make much sense as it is written. dir() returns file/folder names if they match with the argument. So, dir('example*.txt') will return a structure with all files example1.txt, example2.txt and so on (if they exist in the current directory). You can then open them by fopen, such as fid=fopen(file_path(1).name); The '' argument will not open a file and just return -1 (file not found).

In case you get a valid file identifier, you can scroll through the file by the while loop, however, an end is missing here. The initialization lines do not make sense here as they will be rewritten to [] every iteration and not even be touched. The fgetl lines read one line of the file. So first, you read the pattern_size, then the pattern_hour and so on. You then try to find the file named as file_path. Maybe this file should be opened in further lines, but that's not included here.

Hope I could shed some light on this code.

[tabw]

You are right. The code is incomplete because I just post the part I don't understand. I think the missing code is below one. Thanks to both of you, I know the code is to read series of file not single one.

 for counter = 1:file_num
        cellOutline = imread(file_path(counter).name);

[dpb]

What's missing?

doc imread

for the function.

[tabw]

IF the file is not in current directory

file_path = dir('C:\Users\user\Desktop'); % to Detect png file on Desktop

How to use fopen() to open series of file? say, the file are called text1.txt,text2.txt,text3.txt ...

Actaully,the code is like that

file_path = dir('');
fid = fopen('');

while ~feof(fid)

And I don't know what should I put inside the fopen

Answer 1

[dpb]

...Can you make up some example...

See the FAQ

http://matlab.wikia.com/wiki/FAQ#How_can_I_process_a_sequence_of_files.3F

last example on subject.

Answer 2

[Image Analyst]

And fclose() is also missing. This will only read an image file if the image file was written out as ASCII text. Otherwise you should use fread() rather than fgetl() to get the pixels out. And that's only if it's some custom format that imread() doesn't know about.

[tabw]

IF the file is not in current directory

file_path = dir('C:\Users\user\Desktop'); % to Detect png file on Desktop

How to use fopen() to open series of file? say, the file are called text1.txt,text2.txt,text3.txt ...

Actaully,the code is like that

file_path = dir('');
fid = fopen('');

while ~feof(fid)

And I don't know what should I put inside the fopen to open the specific file

[dpb]

Please don't make same comments more than once't--_*most*_ confusing about what is/isn't answered...

[Image Analyst]

Don't use dir() in that case. Just say

folder = pwd; %'C:\Users\user\Desktop'
filePattern = sprintf('%s/*.PNG', folder) % Find PNG image files.
fileNames = dir(filePattern)
for k = 1 : length(fileNames)
  thisBaseFileName = fileNames(k).name;
  thisFullFileName = fullfile(folder, thisBaseFileName);
  fprintf('Now processing %s...\n', thisFullFileName);
end

Answer 3

[dpb]

...IF the file is not in current directory...

Then include it in the argument to dir, of course...

file_path = 'C:\Users\user\Desktop';
d=dir(fullfile(file_path,'text*.txt'));
for i=1:length(d)
  fid=fopen(fullfile(file_path,d(i).name));
  ...

[tabw]

d=dir(fullfile(file_path,'text*.txt'));

??? Undefined function or method 'eq' for input arguments of type 'struct'.

this popped up

[dpb]

My bad...the dir somehow got duplicated in the line defining the directory path...

file_path = dir('C:\Users\user\Desktop');

should, of course, simply be

file_path = 'C:\Users\user\Desktop';

Fixed above, just pointing out the problem.