Dynamic switch in Matlab MAT file

Question

I have a Matlab mat file, which has the following variables:

variable0
variable1
variable2
variable3

Is it possible to dynamically index them and modify, something like this:

function setVariable(obj, variableNum, data)
    obj.matFile.(variable0+variableNum) = data;

end

So, if someone passes 0 variable 0 is modified and if someone passes 3 then variable three. I know this code doesn't work, this is just some example of what I tried. My current solution is to use a switch statement. This is not so good as in the C++ code, I am using indexing like above. I would like the C++ and Matlab to be as close as possible.

ANSWER

I did it this way and it is working:

eval(sprintf('obj.matfile_variable%d = data;', variableNum));

Do you mean how to use the string to load the mat file into a Matlab object? If so, you need matfile(filename) function to create an matfile object. And honestly, I don't think it would be working in just one line. You perhaps need some data checking as well. — Y. Chang
– Y. Chang, Commented Nov 30, 2016 at 14:56

Romano · Accepted Answer · 2016-11-30 07:55:17Z

0

function setVariable(obj, variableNum, data)
    % check if variableNum is numeric
    if isnumeric(variableNum)
        variableNum = num2str(variableNum);
        varName = strcat('variable',variableNum); 
    else
        varName = strcat('variable',variableNum);
    end

    obj.matFile.(varName) = data;


end

This should do the trick.

answered Nov 30, 2016 at 7:55

Romano

131 silver badge7 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Y. Chang Over a year ago

I know it's trivial but I'd like to mention. num2str actually checks the first input argument for string type and return it directly. so you don't need the if...else... statement. Just do the conversion and string concatenation.

Cesare · Accepted Answer · 2016-11-30 10:44:45Z

0

What about using

obj.matFile(variableNum).data = data;

answered Nov 30, 2016 at 10:44

Cesare

756 bronze badges

Collectives™ on Stack Overflow

Dynamic switch in Matlab MAT file

2 Answers 2

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related