How to extract the nth letter from these sample host names using regular expression?

[imthesplunker]

How to extract the nth letter from the host using regular expression?

Sample hosts are :-
host=abcdefpghijkl11 (prod )
host=abcdefsghijkl12 (stg)
host=abcdefdghijkl13 (dev)

[somesoni2 · Accepted solution]

Try like this. e.g. if you want to extract 10th character,

your base search | eval mychar=substr(host,10,1)

Alternatively,

your base search | rex field=host "^\w{9)(?<mychar>\w)"

[imthesplunker]

Thanks !...