In each case, regular expressions can be used to operate on all variables except for a short list.
You can use LOAD with the -REGEXP option to specify a regular expression. Suppose 'mydata.mat' contains the following variables:
myvar1
variable2
var
a
b
abcd
myvar_abc
data
The following code illustrates several examples:
%%Load all variables except 'var'
load mydata -regexp ^(?!var$).
%%Load all variables except 'a' and 'b'
load mydata -regexp ^(?!a$|b$).
%%Load all variables except 'myvar1', 'myvar_abc', and 'data'
load mydata -regexp ^(?!myvar1$|myvar_abc$|data$).
This idea can be extended to clear all variables from MATLAB's workspace except for a few you do not want to clear. For example, if we have the following variables stored in the workspace:
The = 1;
seed = 2;
of = 3;
the = 4;
tree = 5;
seeds = 25;
aseed = 15;
We can clear all variables except the one named 'seed' by executing the following command:
clear -regexp ^(?!seed$).
Alternatively, we can use the following syntax to clear all variables except for 'seed', 'of', and 'the':
clear -regexp ^(?!seed$|of$|the$).
As of MATLAB 7.6 (R2008a), you can use CLEARVARS with the "-except" flag. For example, the expression
clearvars -except A B
will remove every variable from your workspace except the variables "A" and "B".
You may also use the MATLAB Central file called "keep.m" which provides similar functionality:
<http://www.mathworks.com/matlabcentral/fileexchange/loadFile.do?objectId=181>
Note that MathWorks does not guarantee or warrant the use or content of these submissions. Any questions, issues, or complaints should be directed to the contributing author.
