I have a tab-delimited information file, e.g.: 
THAETURQU                 .LLL..RRR
JURYATAUTIOPW             .LLL...LL.RRR
TURIWOWQNQQUTYRIOPWMNHF   L..L..LLLL.LL.R..L.LLLL

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I would really like to be able to pick out the letters from column 1 that correspond to specific combinations from the string in column 2. e.g. for ".LLL" 
 

THAETURQU               .LLL..RRR               THAE
JURYATAUTIOPW           .LLL...LL.RRR           JURY   
TURIWOWQNQQUTYRIOPWMF   L..L..LLL.LL.R..L.LLL   OWQN,PWMF

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Is there an easy way to provide a list of combinations, such as a file: 
 

.LLL
LLLL
.RRR
RRRR

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that would output the corresponding letters in from column 1 in subsequent columns headed, ".LLL", "LLLL", ".RRR", "RRRR"?

I suspect this is really simple, but it would be really helpful, thanks!

In reply to Extracting string based on comparison to second string? by trudy123g

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