Effacer les filtres
Effacer les filtres

How to extract a string before a number?

9 vues (au cours des 30 derniers jours)
Meenal le 30 Août 2022
Modifié(e) : Stephen23 le 20 Mar 2023
Hello everyone, I need to know how to extract a substring from strings given below such that as soon as it encounters a digit, it returns the substring before that.
str = 'abcd-xyzw-1.2.3.zip'
str2 = 'abcd_xyzw_2.3.1.zip'
it should then return the substring as
sub_str = 'abcd-xyzw-'
sub_str2 = 'abcd_xyzw_'
How can it be done?
Thanks in advance

Réponse acceptée

Chunru le 30 Août 2022
str = 'abcd-xyzw-1.2.3.zip';
str2 = 'abcd_xyzw_2.3.1.zip';
idx = regexp(str, '\d');
sub_str = str(1:idx(1)-1)
sub_str = 'abcd-xyzw-'
idx = regexp(str2, '\d');
sub_str2 = str2(1:idx(1)-1)
sub_str2 = 'abcd_xyzw_'
  1 commentaire
Meenal le 30 Août 2022
Thanks !! It worked.

Connectez-vous pour commenter.

Plus de réponses (2)

Karim le 30 Août 2022
You can use the regexp function to find the indexes for the numbers. Then you can split the char array using that index (minus one so that you do not have that first number)
% define the string, note i used a char array as in the OP's question
str = 'abcd-xyzw-1.2.3.zip';
% use the regexp function to obtain the indexes of the numbers
[~,idx] = regexp(str,'(?<!\d)(\d)+(?!\d)','match');
% get the sub string by taking the first characters (minus 1 so that we
% don't copy the first number)
sub_str = str( 1:(idx(1)-1) )
substr = 'abcd-xyzw-'

Stephen23 le 30 Août 2022
Modifié(e) : Stephen23 le 20 Mar 2023
The simple approach using REGEXP, without wasting time fiddling around with indices:
str = 'abcd-xyzw-1.2.3.zip';
sub = regexp(str,'^\D+','match','once')
sub = 'abcd-xyzw-'
This approach also directly works with multiple strings at once (unlike using indexing):
str = {'abcd-xyzw-1.2.3.zip';'abcd_xyzw_2.3.1.zip'};
sub = regexp(str,'^\D+','match','once')
sub = 2×1 cell array
{'abcd-xyzw-'} {'abcd_xyzw_'}


En savoir plus sur Characters and Strings 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