saving variables programmatically using list of variable names

Hi all,

This should be simple but I think my frustration level is keeping me from seeing the path.

I simply want to save some variables on the workspace based on a list of those variable names.

a=1;b=2;c=3

varNames = {'a','b','c'};

save('myMatFile',varNames)

which yields the error 'Error using save. Must be a string scalar or character vector'. (what must be a string scalar? File name? vars? Yes I know, vars, but still TMW...)

so how about

save('myMatFile',cell2mat({'a,','b,','c'});

yielding the more useful error 'a,b,c' is not a valid variable name.

I see where this is going, I must have a properly formatted string array akin to eval inputs. But there really should be an easier way, like my original attempt.

Thanks for the support and letting me rant a bit.

-Chris

[Steven Lord]

That message does seem vague. I've reported that to the development staff.

Answer 1

[Stephen23]

The simple solution is to use a comma-separated list:

varNames = {'a','b','c'};
save('myMatFile',varNames{:})
%                        ^^^ you need this!

https://www.mathworks.com/help/matlab/matlab_prog/comma-separated-lists.html

https://www.mathworks.com/matlabcentral/answers/320713-how-to-operate-on-comma-separated-lists

Tip: when load-ing the file data you should use an output variable (which is a scalar structure):

S = load(...);

[checker]

OK, I've accepted this as a correct answer since it does the job nicely and simply, thanks. intuitively or more importantly per the help for 'save'? Not so much. How is varNames{:} equivalent to a 'string scalar or character vector'?

Answer 2

[Sulaymon Eshkabilov]

Here is an easy solution:

a=1;b=2;c=3;
save('myMatFile.mat','a','b','c')
% Or

a=1;b=2;c=3;
MY_var = {'a','b','c'};
save('myMatFile.mat','MY_var')

[Stephen23]

This code

MY_var = {'a','b','c'};
save('myMatFile.mat','MY_var')

will just save a cell array of character vectors 'a', 'b', and 'c', not the variables with the corresponding names. This does not resolve the original question.