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Uniq using only the first field

 
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# 8  
Old 01-16-2008
Quote:
Originally Posted by smallu
Tytalus

Can you pls explain how it works..whats $1 and $0 and how does it work..Thanks a bunch!
Sure.

$1 is the first field. $0 is the entire record. So...

Basic jist is that you run through each record, and add it to an array (using the first field as a reference) IF the length of the record is greater than the current array entry:

Code:
if ( length($0) > length(a[$1]) ){a[$1]=$0}}

Then you just loop through and print out the contents of the array:

Code:
{for (i in a){print a[i]}}'

HTH
# 9  
Old 01-16-2008
Code:
# sort -k1,1 -u file
1xr1 1xws 1yxt 1yxu 1yxv 1yxx 2o3p 2o63 2o64 2o65
1y8y 2c68 2c69 2c6i 2c6k 2c6m 2c6o
1zlt 2br1 2brb 2brn 2bro 2cgu 2cgv 2cgx

 
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