MATLAB: Is there a function like cat in MATLAB that can be used to concatenate two files into a third file

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Is there a function like "cat" in MATLAB that can be used to concatenate two files into a third file?

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There is no builtin MATLAB command like the "cat" utility command that will concatenate files into a new one. However, you can use the "system" function in MATLAB to execute operating system commands, such as "cat". For example, to concatenate two TXT files into a third one in MATLAB, the following code snippet using the "system" function will work:

>> command = 'cat test1.txt test2.txt > test3.txt';
>> status = system(command);

The above code snippet executes the command to concatenate the first two files into a new file. For more information about how to use the system function in MATLAB, please view the documentation page linked below:

https://www.mathworks.com/help/matlab/ref/system.html

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MATLAB: Renaming files using MATLAB

From MATLAB, you can use the "movefile" function to rename files on your machine:

https://www.mathworks.com/help/releases/R2020a/matlab/ref/movefile.html

For more information on managing files and folders in MATLAB see this documentation:

https://www.mathworks.com/help/releases/R2020a/matlab/matlab_env/manage-files-and-folders.html

Alternatively, you can use the "system" command which executes on the local operating system.

On Windows using CMD, the "rename" command works like this:

C:> rename  file_path  new_name
C:> rename  C:\Temp\file1.txt file2.txt

So in MATLAB, from the directory with the file you could execute:

>> system("rename " + "old_name.txt" + " " + "new_name.txt")

If the file names contain spaces, this can confuse the operating system, so a more robust approach is to wrap each file name in double quotes like this:

>> system("rename " + '"' + "old name.txt" + '" "' + "new name.txt" + '"')

This produces a system command like this:

C:> rename "old name.txt" "new name.txt"

To use MATLAB variables for the old and new file names you can use these MATLAB commands:

>> old_path_to_file = "C:\Temp\test a.txt";

>> new_filename = "test b.txt";

>> cmd = "rename " + '"' + old_path_to_file + '" "' + new_filename + '"';

>> system(cmd);

On a Linux or macOS (Unix) system, this would be:

>> old_path_to_file = "/tmp/test a.txt";
>> new_filename = "test b.txt";
>> cmd = "mv " + '"' + old_path_to_file + '" "' + new_filename + '"';
>> system(cmd);

MATLAB: Are some country-specific paper types not included in MATLAB 7.0 (R14)

This bug has been fixed in Release 14 Service Pack 3 (R14SP3). For previous product releases, read below for any possible workarounds:

MATLAB has a limited list of pre-defined countries for which it sets the default paper type to "A4" and default paper units to "centimeters". For all other countries, "usletter" and "inches" will be used respectively. These settings are created in the "hgrc.m" file.

There are two methods to resolve this issue and set the default value of these properties for your system.

1. If you are an individual user, especially on a network installation of MATLAB, it is recommended that you add the following line in your "startup.m" file (if a "startup.m" file does not exist on your system, create a new one and place it on the MATLAB path):

set(0,'DefaultFigurePaperType','A4')
set(0,'DefaultFigurePaperUnits','centimeters')

This method is preferred for individual users since it will carry over between releases of MATLAB (upgrading MATLAB will preserve your "startup.m" file, but will over-write "hgrc.m"). This also allows "hgrc.m" and "matlabrc.m" to be used by network administrators to make system-wide changes without over-writing individual users' settings. This setting is also independent of your system's country setting, thus, even if your country is set to US, you can still use this method to set the default paper type and paper units in MATLAB.

2. If you are a network administrator and want to make a system-wide change, you can edit the "hgrc.m" file. The list of countries for which MATLAB sets the paper size to "A4" can be found in this file. To add your country code to this list, follow these steps:

a. Find the two-letter ISO 3166 short name for your country, i.e., the ISO 3166-1-alpha-2 code which can be found at the following address:

https://www.iso.org/obp/ui/#search

b. Type "edit hgrc" at the MATLAB prompt. (For reference, the "hgrc.m" file resides in $MATLAB\toolbox\local\, where $MATLAB is the MATLAB root directory; the file can be located on your system by typing "which hgrc" at the MATLAB prompt).

c. Scroll down to the line that reads

if usejava('jvm') && ~exist('defaultpaper','var')
  if any(strncmpi(char(java.util.Locale.getDefault.getCountry), ...
           {'gb', 'uk', 'fr', 'de', 'es', 'ch', 'nl', 'it', 'ru',...
           'jp', 'kr', 'tw', 'cn', 'cz', 'sk', 'au', 'dk', 'fi',...
           'gr', 'hu', 'ie', 'il', 'in', 'no', 'pl', 'pt',...
           'ru', 'se', 'tr', 'za'},2))
    defaultpaper = 'A4';
    defaultunits = 'centimeters';
  end
end

d. You need to add your country code to this list. For example, if you were adding Liechtenstein (ISO 3166 code "li"), you would edit this code to read:

if usejava('jvm') && ~exist('defaultpaper','var')
  if any(strncmpi(char(java.util.Locale.getDefault.getCountry), ...
           {'gb', 'uk', 'fr', 'de', 'es', 'ch', 'nl', 'it', 'ru',...
           'jp', 'kr', 'tw', 'cn', 'cz', 'sk', 'au', 'dk', 'fi',...
           'gr', 'hu', 'ie', 'il', 'in', 'no', 'pl', 'pt',...
           'ru', 'se', 'tr', 'za','li'},2))
    defaultpaper = 'A4';
    defaultunits = 'centimeters';
  end
end

e. Save the file.

f. Exit MATLAB and restart for the changes to take effect.

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Related Solutions

MATLAB: Renaming files using MATLAB

MATLAB: Are some country-specific paper types not included in MATLAB 7.0 (R14)

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