How can i edit a .mat file
276 views (last 30 days)
Show older comments
I have a .mat file name.mat. It contains information such as and when I open it the import wizard opens. now say the data in the import wizard is as follows:
|var_name | Ixx | Iyy | Izz
A 1 2 3
B 4 5 6
C 7 8 9
Now say I wanted to go in and update the numbers to 2-10 -- how do I do this? Or, how can I create a .mat file?
I tried using the import wizard and creating my own, but when I do, it doesn't include having the variable names in the same table because they're letters and not numbers.
Thanks
0 Comments
Accepted Answer
Image Analyst
on 11 Jan 2013
You have to read it all in:
storedStructure = load('name.mat');
A = storedStructure.A;
B = storedStructure.B;
C = storedStructure.C;
Then change things:
A = [1 2 3];
B = rand(1,3);
C = randi(100, 3);
Then save it back:
save('name.mat', 'A', 'B', 'C');
2 Comments
Arthur Vieira
on 30 Apr 2021
If I have variables in my workspace that I don't want to loose (i.e. can't load the .mat in), how can I update what's in the .mat file? Including deleting a variable within a .mat file? I could load them with:
var = load('myData.mat');
But that makes 'var' a structure. And you can't save variables within structures for some reason. I'm confused on how you're meant to use .mat files.
Steven Lord
on 30 Apr 2021
After you load the variables from the MAT-file into a struct array and modify the fields of that struct, call save with the '-struct' option and the name of the struct array.
cd(tempdir)
v = struct('x', 1:10, 'y', @sin, 'z', "abracadabra");
save('mymatfile.mat', '-struct', 'v')
whos -file mymatfile.mat
The MAT-file does not contain the struct v but contains three variables, one for each field in v.
More Answers (1)
Azzi Abdelmalek
on 11 Jan 2013
Edited: Azzi Abdelmalek
on 11 Jan 2013
a=10; v=magic(4)
save filename a v
To load your file
load filename
2 Comments
Azzi Abdelmalek
on 11 Jan 2013
Edited: Azzi Abdelmalek
on 11 Jan 2013
fid=fopen('file1.txt')
x=textscan(fid,'%s %f %f %f')
fclose(fid)
out=cell2mat(x(2:end))
% to get the characters
d=x(1)
lett=d{:}
See Also
Categories
Find more on Workspace Variables and MAT-Files in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!