Creating a variable from part of a string

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I have a string:
x='dr_1e-2_A1_OFF_A2_OFF.txt';
Is there a way to create variables from this string?
How can I set
dr = 1e-2
by only referring to the string? How can I set
A1 = 0 (since Off)
by only referring to the string?
Then if I want to create a title from the variables, could I?
Like:
title('dr = ' insert dr variable )
  1 Comment
Stephen23
Stephen23 on 7 Nov 2018
"Then if I want to create a title from the variables, could I?"
You certainly could... but this is not recommended. Magically creating variable names is one way that beginners force themselves into writing slow, complex, buggy code which is hard to debug. Read this to know why:

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Accepted Answer

Stephen23
Stephen23 on 7 Nov 2018
Edited: Stephen23 on 7 Nov 2018
I recommend that you use a structure instead of magically accessing variable names:
>> x = 'dr_1e-2_A1_OFF_A2_OFF.txt';
>> [~,N] = fileparts(x);
>> C = regexp(N,'_','split');
>> S = struct(C{:});
>> S.dr
ans = 1e-2
>> S.A1
ans = OFF
>> S.A2
ans = OFF
You can easily add a conversion to numeric as well:
>> [~,N] = fileparts(x);
>> C = regexp(N,'_','split');
>> V = str2double(C);
>> X = ~isnan(V);
>> C(X) = num2cell(V(X));
>> S = struct(C{:});
>> S.dr
ans = 0.010000
"Then if I want to create a title from the variables,could I?"
Of course, read about fieldnames and dynamic field names:
  3 Comments
James Tursa
James Tursa on 7 Nov 2018
Yikes! The rest of my edited comment didn't make it, re the splitting and struct stuff ...

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