R regex to validate user input is correct.

Posted by John on Stack Overflow See other posts from Stack Overflow or by John
Published on 2010-03-16T00:29:14Z Indexed on 2010/03/16 0:29 UTC
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I'm trying to practice writing better code, so I wanted to validate my input sequence with regex to make sure that the first thing I get is a single letter A to H only, and the second is a number 1 to 12 only. I'm new to regex and not sure what the expression should look like. I'm also not sure what type of error R would throw if this is invalidated?

In Perl it would be something like this I think: =~ m/([A-M]?))/)

Here is what I have so far for R:

input_string = "A1"
first_well_row = unlist(strsplit(input_string, ""))[1]  # get the letter out
first_well_col = unlist(strsplit(input_string, ""))[2]  # get the number out

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R regex to validate user input is correct. - Developer IT

R regex to validate user input is correct.

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