Hi all,

I have a list of node pairs separated with a comma and also, associated with their respective values. For example:

b0015,b1224    1.1
b0015,b2576    1.4
b0015,b3162    2.5
b0528,b1086    1.7
b0528,b1269    5.4
b0528,b3602    2.1
b0948,b2581    3.2
b1224,b0015    1.1
b1086,b0528    1.7

b0015,b1224    1.1
b0015,b2576    1.4
b0015,b3162    2.5
b0528,b1086    1.7
b0528,b1269    5.4
b0528,b3602    2.1
b0948,b2581    3.2

Try:

awk '{  split($1, f, /,/)
        if((f[2]","f[1]) in o) next
        o[$1]
        print
}' input

This works for me (using gawk):

gawk -F',| ' '!(a[$1,$2]++ + a[$2,$1]++)'

Thanks for the help but, although it successfully removes the duplicates in column 1, it does not print last (value) column along.

Broken awk? See the hints posted by Don Cragun.

This should work with any recent awk ( /usr/xpg4/bin/awk or nawk on Solaris systems); it doesn't use any non-stamdard gawk extensions.

Unlike the script I gave, this won't print any duplicated nodes when the nodes.

Perhaps there are tabs present in the input file?

awk -F'[, \t]' ...