Creating a variable from part of a string

3 vues (au cours des 30 derniers jours)
Benjamin
Benjamin le 7 Nov 2018
Modifié(e) : Stephen23 le 7 Nov 2018
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 commentaire
Stephen23
Stephen23 le 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:

Connectez-vous pour commenter.

Réponse acceptée

Stephen23
Stephen23 le 7 Nov 2018
Modifié(e) : Stephen23 le 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 commentaires
Stephen23
Stephen23 le 7 Nov 2018
Modifié(e) : Stephen23 le 7 Nov 2018
Thank you! It just removes the file extension...
James Tursa
James Tursa le 7 Nov 2018
Yikes! The rest of my edited comment didn't make it, re the splitting and struct stuff ...

Connectez-vous pour commenter.

Plus de réponses (0)

Catégories

En savoir plus sur Workspace Variables and MAT-Files dans Help Center et File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by