Could not save my variable in a specific name

I am trying to save Z in a spceific file name ... I am geting error saya

Error using save

Must be a string scalar or character vector.

Here is my code ... any idea ?

filename=['synthetic_data.' num2str(1) '.mat'];

save (filename, Z);

Thank you

Answer 1

[Sulaymon Eshkabilov]

Two very tiny flaws (e.g.: unnecessary "." and necessary ' ') in your used syntax and here is the correct syntax:

filename=['synthetic_data' num2str(1) '.mat'];
save (filename, 'Z');  % Z is already residing in your workspace

[Seereen]

Ok I figure out my problem ... Thank you :)