MATLAB Answers


Saving/storing data from plot

Asked by James Hendren on 19 Jul 2013
Accepted Answer by dpb

I'm running a gui. I have 2 axes, both with the same x-axis(frequency), but the y axes are E1 & E2 respectively. After plotting them, I need a push button to save the data into a .dat file with three columns (freq, E1,E2). Then, I need a method to import the saved/stored data back into the gui using another push button. Can anyone help? thanks in advance


I was just commenting back

on 22 Jul 2013

Ahhh, so...sorry; thought you were having troubles yet.

what is the difference between command and functional form?


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2 Answers

Answer by dpb
on 19 Jul 2013
Edited by dpb
on 22 Jul 2013
 Accepted answer

If the point is only to save the data for recall at a later time then just use SAVE and LOAD and save as .mat file. You automagically get full precision

For SAVE button callback would contain one of the following

save FEfile f E1 E2           % command form
save('FEfile' 'f' 'E1' 'E2')  % functional form

Need to make the data available of course; use [set|get]appdata to get it between one callback and another or retrieve it directly from the plot handles or other fashion.

The IMPORT button callback would contain either

load FEfile f E1 E2           % command form
load('FEfile' 'f' 'E1' 'E2')  % functional form

The SAVE function adds sufficient info into the file that the variable names/sizes are known. The LOAD will retrieve the variables named into those names in the workspace.

If you really, really must have ASCII, look at dlm[write|read] and friends. Look at

help iofun

note the list under File Import/Export functions and select what seems most suitable to your purposes.


Answer by James Hendren on 22 Jul 2013

I am having a problem. I had the frequency and E1 and E2 as globals, so would the format for saving them on the push button be different? Does there need to be a set|get appdata for that? If so how would I do it?


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