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I have a program that reads in a really large Excel file and creates some large variables. This runs out of storage if I try to run it multiple times in a row, which makes sense, i.e.:

large_program; large_program

will crash. However, what I don't understand is why

large_program; clear all; large_program

will also crash; in order to run it multiple times, I have to restart MATLAB each time. Does MATLAB not actually clear all variables? Or is this a fragmentation of memory thing?

braX
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Tim Hazard
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  • You can test if its related to fragmentation by doing `large_program; clear all; pack; large_program` – learnvst Jul 13 '12 at 20:32
  • @learnvst: I think `pack` will only defragment memory of assigned data... So it's useless after a `clear all` – Amro Jul 13 '12 at 20:47
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    This is related: [Matlab: Free memory is lost after calling a function](http://stackoverflow.com/a/3301971/97160) – Amro Jul 13 '12 at 20:49

1 Answers1

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Matlab can indeed hold onto some variables and other settings "under the hood". I have the following set up as a short-cut to purge it back to a "just switched on" state (the one that can really catch you out is that clear functions is not a subset of clear all).

restoredefaultpath;
clc;
clear all;
close all;
clear functions;
bdclose('all');
fclose('all');
BigA
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