save the output of system command using matlab

Hello! I am executing a system command via matlab. in the command I am writing the output to a file. when running the code I can find the generated file but I want that file be passed to Matlab as a variable, how can I get to this ? see the code bellow (I want something so that fileA.txt be attributed to cmdout or any thing similar so Matlab can recognize and work directly with the file)

   command = 'MyInstuction >fileA.txt';
   [status,cmdout] = system(command);

Answer 1

[Steven Lord]

Use concatenation or sprintf to assemble a command for use with the system function that needs to include information from a variable.

myfilename = 'fileA.txt';
command = ['MyInstuction > ' myfilename]
% I left off the semicolon on the previous line deliberately
% so you can see the command to be executed
[status,cmdout] = system(command);

Answer 2

[Walter Roberson]

Leave off the redirection. Just

     command = 'MyInstuction';
    [status,cmdout] = system(command);

Answer 3

[Ano]

thank you for your reply!

• I have made the change that you have suggested . it takes a long time since the generated file is very large. any other alternatives ??!!
• I get cmdout as a 'char', how can I extract my data from it or how can I know where my data is placed in cmdout?Best regards!

[Jan]

Please post comments in the comment section, not as an answer. Thanks.

How can the generated file be large, if you omit the generation of a file? How could we know, where you can find the wanted parts of the replied string?

[Ano]

thank you Jan Simon, I posted the comment as an answer because there is no notification for comments and the time response is really very critical!

[Jan]

If the repsonse is time critical, please answer my questions for clarifications. I'd really like to assist you, but I cannot guess, "how can I know where my data is placed".