Discovering patterns in textual strings

The answer is, of course, using regular expressions and/or libraries
therefor. However, I do not think you have defined your problem
sufficiently. Some questions I have:

1. Do possible patterns to be matched always appear at the beginning
of your strings?

2. Always together between specified separators ("_"  in your
example); or one of several specified separators; or otherwise?

3. Do spaces or other nonprinting characters occur in your strings?

e.g. would

abc_something
this.is_a long stringwithabcinthemiddle

be considered matching?
There are undoubtedly other possibilities that I've missed.

You may also find it useful to check this "task view" out for possibilities:
https://cran.r-project.org/web/views/NaturalLanguageProcessing.html

Cheers,
Bert


Bert Gunter

"The trouble with having an open mind is that people keep coming along
and sticking things into it."
-- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )

R Help Forum



Is there a R library (or a way) that I can extract unique character strings,
or repeating patterns in textual strings.  Say for example I have the
following records:



Abc_1234_kjhksh_276

Abc

Abc_1234_lakdofyo_324

Bce_876_skdhk_*&^%*&

Bce

Bce_454



And I would like to see the following results

Abc

Abc_1234

Bce





Jeff Reichman


        [[alternative HTML version deleted]]

______________________________________________
R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.