Fast method to store workspace variables into another worspace variable?

Hi- i would like a fast method to store all workspace variables into another workspace variable.

My current slow method is this...

tmp=tempname;
save(tmp)
x = load(tmp);
delete(tmp)

any better ideas?

[Walter Roberson]

I think you will find that that method does not work when it comes to objects, and I think you will find it doubles the memory instead of sharing it (until the next write to the variables anyhow.)

Answer 1

[Sean de Wolski]

You could pass them into the function the typical way

function y = some_fun(tmp,x)
y = x*tmp;

Or you can use setappdata/getappdata, though this can be dangerous. It is very fast though. To do it, I recommend packing everything into a struct or a cell and saving it as some obscure name. I have had to do this for big variables passed between functions that are called (literally) billions of times.

S.tmp = tmp;
S.x = x;
setappdata(0,'S_2be_used_in_foobar',S);

%in foobar
function y = foobar()

S = getappdata(0,'S_2be_used_in_foobar'); %pull in
tmp = S.tmp; %extract
x = S.x
y = tmp*x;

Just note this can be very dangerous and is generally recommended against. To safeguard it, use a long name with lots of underscores and numbers.

[Darin McCoy]

why is it dangerous? and i assume if you wanted to get all the workspace variables, you would do a loop based on the content of the

who

function?

[Sean de Wolski]

If you're still wondering. Storing data to the root directory is dangerous since that's where MATLAB stores some important things that if overwritten or reset could cause fatal/difficult to trace errors.

[Sean de Wolski]

And yes, you could do a loop, I would recommend using the loop to pack everything into a struct using the fieldnames option.