How to clear all variables except one or two

Diego Zegarra

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Jan 31, 2009, 6:40:17 PM1/31/09

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I have a code that creates many variables and at each iteration I want to clear all the variables except for one or two. Is this possible without specifying clear A, clear B and so on for every variable?

I know clear all deletes them all but I need to keep one of them.

Thanks

Matt Fig

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Jan 31, 2009, 7:11:01 PM1/31/09

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Do a search on the FEX for: keep

Ak6<k]eihkh*aca{dIppd#ldkak]lijq{{]u_kj]{{]{_^r]gp]U#e{{^qa

Diego Zegarra

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Jan 31, 2009, 7:37:01 PM1/31/09

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Actually I found a way that can be done easily, this for anyone out there needing this info,

clearvars -except v1 v2 ... clears all variables except for those specified following the -except flag. Use the wildcard character '*' in a variable name to exclude variables that match a pattern from being cleared. clearvars -except X* clears all the variables in the current workspace, except for those that start with X, for instance.

Matt Fig

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Jan 31, 2009, 7:51:02 PM1/31/09

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What version are you using? I don't have a clearvars command.

k{{_l{A{ueUpah6]ajhdjdqie{kk#^]qcga{p^#*{]{k]airIp]dkk_]<]l

Diego Zegarra

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Jan 31, 2009, 8:23:02 PM1/31/09

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R2008a, I think it just came out starting this version.

Jan Simon

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Feb 1, 2009, 5:57:01 PM2/1/09

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Dear Diego Zegarra!"

> I have a code that creates many variables and at each iteration I want to clear all the variables except for one or two. Is this possible without specifying clear A, clear B and so on for every variable?

Let the names of all variables, which should be cleared, start with a specific string, e.g.
"away_". Then "clear away_*" deletes them from memory.

By the way: clearing and recreation of variables is very time consuming. It could be more effective to use a cell instead of a cloud of variables.

Good luck, Jan Simon

Steven Lord

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Feb 2, 2009, 10:49:53 AM2/2/09

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"Diego Zegarra" <dieg...@gmail.com> wrote in message
news:gm2thm$mcb$1...@fred.mathworks.com...

> R2008a, I think it just came out starting this version.

You're correct, CLEARVARS was introduced in release R2008a.

http://www.mathworks.com/access/helpdesk/help/techdoc/rn/brjk1q5-1.html

--
Steve Lord
sl...@mathworks.com

Gireg

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Jun 25, 2014, 10:39:09 AM6/25/14

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"Diego Zegarra" wrote in message <gm2nh1$4hu$1...@fred.mathworks.com>...

> I have a code that creates many variables and at each iteration I want to clear all the variables except for one or two. Is this possible without specifying clear A, clear B and so on for every variable?
>
> I know clear all deletes them all but I need to keep one of them.
>
> Thanks

Hi Diego,
I was just looking for the same functionality today, that's why I answer you so late. You certainly have found a solution since. I have find a way that may be usefull to other Matlab users, so here is my solution:

clearvarlist = ['clearvarlist';setdiff(who,{'vartokeep1';'vartokeep2';'vartokeep3'})];
clear(clearvarlist{:});

dpb

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Jun 25, 2014, 11:03:03 AM6/25/14

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There's also the -regexp pattern-matching alternative. Limited only by
your creativity in writing the regular expression.

--

Loren Shure

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Jun 27, 2014, 1:46:38 PM6/27/14

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"Gireg " <lani...@hotmail.fr> wrote in message
news:loemud$8p2$1...@newscl01ah.mathworks.com...

It's much simpler than that:

clearvars -except vartokeep1 vartokeep2 var2keep3

--
--Loren

http://blogs.mathworks.com/loren

Blake

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Jun 24, 2015, 10:02:10 AM6/24/15

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"Diego Zegarra" wrote in message <gm2qrd$r1$1...@fred.mathworks.com>...

> Actually I found a way that can be done easily, this for anyone out there needing this info,
>

I DID need the info, and you have saved me a lot of time. Thanks!