How to save -struct

Hey, I'm having trouble saving this struct.

I've tried

save('datafile.mat','mati','-struct','materials');

when my code is something like:

mati = 1;
materials(mati).name = input('','s');
    disp(strcat('Introduce the properties of the material',32,materials(mati).name,32,'in SI units.'));
    disp('Density [Kg/m3]');
    materials(mati).properties(1) = input('');
    disp('fusion temp [K]');
  materials(mati).properties(2) = input('');
    disp('stress blab la [MPa]');
  materials(mati).properties(3) = input('');
    disp('Tensão de ruptura [MPa]');

But I get this error:

Error using save
The argument to -STRUCT must be the name of a scalar structure variable.

Answer 1

[Matt Fig]

According to the help for SAVE, you need to call like this:

save(filename, '-struct', structName, fieldNames)

Note that -struct is the second argument, not the third... But I wonder if all you need is this:

save('datafile.mat','materials');

For example:

clear all  % Start with a clean slate
S.name = 'Iron';  % Build a structure
S.density = 2700;
S.CS = 'Fe';
save('myIron.mat','S')  % Save the structure
clear all  % Clear to make sure struct is gone.
load('myIron.mat')  % Load it.  (Also, X=load(...) is preferred)
whos  % See if we have our structure back...
  Name      Size            Bytes  Class     Attributes

    S         1x1               548  struct

Answer 2

[Oleg Isaev]

https://www.mathworks.com/help/matlab/ref/matlab.io.savevariablestoscript.html