Saving to .mat without additional struct.

I have that structure

test = 

  struct with fields:

           F0: 243000
            I: [3×3 double]
          I_1: [3×3 double]
          I_X: 5550000
         I_XZ: 33000
            %[...]
            m: 160000
            

that i want to save 'as it is'

uisave('test')

I save it as name ('test2'), i load it back and i go this

aircraftdata = load('test2.mat')

aircraftdata = 

  struct with fields:

    test: [1×1 struct]

What i want is a structure like this :

    aircraftdata = 

  struct with fields:

           F0: 243000
            I: [3×3 double]
          I_1: [3×3 double]
          I_X: 5550000
         I_XZ: 33000
            %[...]
            m: 160000
            

The whole point is saving the structure untouched and load it with a new name

Answer 1

[Steven Lord]

When you save the struct array, specify the '-struct' option. This will save each of the struct fields separately in the MAT-file. When you call load with an output argument, each of those separate pieces of data from the MAT-file will become fields of the new struct.

S = struct('theAnswer', 42, 'magicMatrix', magic(5), 'nephews', ["Huey", "Dewey", "Louie"])

S = struct with fields:
      theAnswer: 42
    magicMatrix: [5×5 double]
        nephews: ["Huey"    "Dewey"    "Louie"]

cd(tempdir)
name = 'temporaryMatfile.mat';
save(name, '-struct', 'S')
whos('-file', name) % Individual variables

  Name             Size            Bytes  Class     Attributes

  magicMatrix      5x5               200  double              
  nephews           -                258  string              
  theAnswer        1x1                 8  double              

data = load(name)

data = struct with fields:
      theAnswer: 42
    magicMatrix: [5×5 double]
        nephews: ["Huey"    "Dewey"    "Louie"]

Compare with:

name2 = 'otherTemporaryMatfile.mat';
save(name2, 'S')
whos('-file', name2) % The struct was stored intact

  Name      Size            Bytes  Class     Attributes

  S         1x1               970  struct              

data = load(name2)

data = struct with fields:
    S: [1×1 struct]

data.S

ans = struct with fields:
      theAnswer: 42
    magicMatrix: [5×5 double]
        nephews: ["Huey"    "Dewey"    "Louie"]

[Gabriel ROUX]

Thank you very much,

It works fine, but i doesn't suits my needs. I'm working with "uisave()" because it is more user-friendly with AppDesigner. Does uisave allows '-struct' options ? Another issue is that with 'uisave we have no return about what is the filename chosen by the user and what is it's path, so i cannot apply further processing once he's done.

[Steven Lord]

I don't believe uisave offers the '-struct' option. You could try using a different tool, like uiputfile, to select the file to which you want to save. Once you have the file name and path information, use fullfile to construct the fully qualified name and pass name that into save.

Answer 2

[Steve Eddins]

Try this:

s = load("test2.mat");
aircraftdata = s.test;

Answer 3

[Gabriel ROUX]

I have it https://fr.mathworks.com/matlabcentral/answers/330397-how-can-i-save-some-fields-of-a-struct-using-uisave-function#answer_259211