I tried to read .jpg files from a folder in matlab using dir command. But I am not getting them from the first image stored in the folder. Instead it started from 10th image. I want to know how to read the files serially starting from the beginning.
I am almost certain that if you are using a simple enough command, it will give you all files that are there. However, this may not seem to be the case because of this little line in the description:
Results appear in the order returned by the operating system.
This may mean, that you will first see files like 1, 100, 1000,1999 and only later a file with numer 2. Of course you can sort the results after you have collected them, and then process them in your desired order.
For completenes, one would like to have something like:
dir *.jpg
or if you want to be sure to catch everything that even remotely resembles .jpg:
dir *.*j*p*g*
Related
I'm looking for a way to automate archiving where after I plug my two external drives I can copy all my resources. The problem is that I have different file structures on my laptop and on both external drives so I need to select specific folders to be copied. It means that I can't select one root folder and copy it straightforward. I tried to find a way to declare more than one path in the cp command and in the copy command, without success. An example path:
/my_programming_stuff
/folder1
/folder2
/folder3
/folder4
I want to select only the first 3 folders to copy them into external drive1 and external drive 2. The idea is to create a .bat file that will copy everything at once ( in the best case scenario it will be copied simultaneously on both external drives, so it will be much faster). Another problem is that there needs to be a bypass the ntfs long path limitations (max. 260 characters).
Flags that I want to use:
Copy the files and directories and all of their attributes,
including ownerships and permissions.
Recursively copy directories and their contents.
When copying files from one directory to another, only
copy files that either doesn't exist or are newer than the
existing corresponding files, in the destination
directory.
data verification (so it's certain that the copy was verified)
progression bar with time eta
Until now I was using Total Commander to do this but every day I need to pick only a few folders to be copied which takes time and is inefficient.
I have experience with Bash and PowerShell but I am not sure how to handle this topic.
Create a static batch file with robocopy commands. I think /copyall is the only switch you need to specify for all this. Other defaults should satisfy requirements.
https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/robocopy
I think your time will be better spent learning how to use either FastCopy or FreeFileSynce. I used FreeFileSync some years ago but got disgusted with the it's constantly changing format of its xml file used for starting a backup, so I switched to FastCopy. But it looks like FreeFileSync may be getting their act together and I aim to do some experiments over the summer to see if I want to switch back to it.
Both can handle the long filename format issues, both can be executed by a batch file, both seem to have a lot of quality, but FreeFileSync has more features - and more bloated because of the features. But speed wise, I think FastCopy is probably one of the better products out there and very streamline in use and design.
I have about 1500 image files in a folder and listing all using dir() last too long and sometimes crashes the AppDesigner. Is there a way to list only the first or the first n images at a given time?
No, this is not possible, because dir essentially is a wrapper of a operation system function (such as the Windows dir and the Linux 'ls'). So now you have two (actually three but you're not gonna like at least one of them^^) options
it shouldn't cause much trouble to call 1500 files. Have a look if it is really the dir command, which causes trouble. Use the Rund and Time functionality in the Editor
use dir with a pattern. Eg. lst = dir() returns an array of structs with everything in the current folder -- including . and .., which are usually nothing you need. Use lst = dir('*.m') instead to get all .m files. In your case, it can be lst = dir('d_Seite_*.jpg'). I am not sure if that saves you much time but at least memory
restructure how your data (images) is stored so that there are less files available. You could run a background task that moves only the n latest files into the folder latest_files and moves them out again if there are newer ones...
For this project we have been given code, and will be changing some inputs and assumptions. Thus, I already possess the original codes, but just changing all the creator's file paths to match my own computer is yielding me a lot of trouble. The following, and many variations of, continually yield errors.
load \Users\myname\Library\Documents\...
The error is
Error using load
'Unable to read file
\Users\myname\Library\Documents...'.
No such file or directory.
My files are stored in my Documents. Another person in my group on windows has used
load C:\Users\hisname\Desktop\...
Is there something I'm missing in my line, similar to the C drive but on Mac? Is my code just completely wrong, I'm able to load files in R quite easily, but Matlab is posing a huge hurdle. I have no experience with Matlab and have been asked simply to run this code.
On the Mac, path components are separated by /, not \. Thus, you should type
load /Users/myname/Documents/filename.mat
You can use the location bar at the top of the command window to change to the directory where your file is located, and then you can type
load filename
to load filename.mat.
Also, are you sure you have a Documents directory under Library? Why?
To run code from a file called "my_file.m", than just open your Matlab and type run my_file.m. This will run your script in the Command Window.
The load function is used, if you want to load a .mat file. These are normally files, where variables from your workspace are stored.
I am trying to read output of one program into another program. But in each of these programs, I am using some input data which is being loaded from those respective directories. For example,
In program 1, I load some text files and run the code for some array of outputs.
In Program 2, I load some other text files and run the program. And in program 2 I also want to use data which is output of program 1.
Text files in program 1 and 2 are at different locations.
Can you suggest me to handle this issue?
As mentioned in the comments, you only need to use the absolute path to your files:
load('C:\...\dataFolder\dataFile.mat')
This way you can reach it independently on the current working folder in MATLAB.
I have a script in MATLAB that outputs various files, including NIFTI (MRI images) files and text log files. Sometimes the output files that are created have their file permissions set to no read or write for anyone, including the file owner, and this appears to occur randomly.
This normally isn't a problem unless it occurs with the logs, as it leads MATLAB to endlessly recurse as it tries to write the error to the logs. Unfortunately, I haven't been able to find anyone who has experienced similar behavior from any program, including MATLAB.
The script, input files, and output files are all located on a NAS drive connected to a server running Ubuntu 14.04, so I'm wondering if this is a problem with the script (probably not because it happens intermittently regardless of input), the matlab environment, or the NAS drive.
I'm not sure why yoru fileattributes/permissions are changing, but I know the solution. You want file attributes if you know chmod from unix this should be familiar, if not you will still be fine
something like this will make your files writeable for all user groups on a unix (ubuntu) system
fileattrib('/home/work/results/my_file.log','+w','a')
edit
since these files are non-existant this may work better. Simply use fopen with the 'w+' flag. Which means write mode for appending. The + will also create the file if it doesn't exist(and you have permission to create files in the specified directory)
fid = fopen('my_new_log.txt','w+');
fprintf(fid,'some strings for my file');
fclose(fid);
it is also important you make sure to close the file after you are done.