how to append a mat file
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Hi - I am using the save command to save a variable in my workplace which is two rows and one column worth of data (2 by 1). However, I would like the 'append' command to move one column the right evertime it is run (as not to replace my first column worth of data), however reading the 'save' help file, it only 'appends' if it is ASCI but does not 'append' when it is a .mat file. How do I prevent my data from being overwritten and instead having new data keep being added to the right (this way, I can just load it, and plot all of first row and use the second row as 'labels' (for the legend))...
save(data.mat,datacell,'-append')
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Answers (3)
Walter Roberson
on 17 Mar 2019
You cannot do that with save()
Have a look at https://www.mathworks.com/help/matlab/ref/matfile.html
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nas illmatic
on 17 Mar 2019
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Walter Roberson
on 17 Mar 2019
Sure. just load the appropriate variable from the mat file , make the change and save with append (which does work for mat files by replacing the specified variables and leaving the rest in place . ) The built in functionality to handle that is matfile() but you can write your own function .
nas illmatic
on 17 Mar 2019
Edited: nas illmatic
on 17 Mar 2019
4 Comments
Maxwell Rosen
on 2 Aug 2021
I think you have to delete that last save() function. Matlab automatically appends your array that you opened m. See the function https://www.mathworks.com/help/matlab/ref/matlab.io.matfile.html in the example Load and Save Parts of Variables
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