How to print a line with no field separator in awk? - regex

Question

I have data like this (file is called list-in.dat)
a ; b ; c ; i
d
e ; f ; a ; b
g ; h ; i
and I want a list like this (output file list-out.dat) with all items, in alphabetically order (case insensitive) and each unique item only once.
a
b
c
d
e
f
g
h
i
My attempt is:
awk -F " ; " ' BEGIN { OFS="\n" ; } {for(i=0; i<=NF; i++) print $i} ' file-in.dat | uniq | sort -uf > file-out.dat
But I end up with all antries except those lines which has only one item:
a
b
c
e
f
g
h
i
How can I get all (unique, sorted) items no matter how many items are in one line / if the field separator is missing?

Answer 1

Using gnu-awk:
awk -F '[[:blank:]]*;[[:blank:]]*' '{
for (i=1; i<=NF; i++) uniq[$i]
}
END {
PROCINFO["sorted_in"]="#ind_str_asc"
for (i in uniq)
print i
}' file
a
b
c
d
e
f
g
h
i
For non-gnu awk use:
awk -F '[[:blank:]]*;[[:blank:]]*' '{for (i=1; i<=NF; i++) uniq[$i]}
END{for (i in uniq) print i}' file | sort

Answer 2

awk -F' ; ' -v OFS='\n' '{$1=$1} 1' ip.txt | sort -fu
-F' ; ' sets space followed by ; followed by space as field separator
-v OFS='\n' sets newline as output field separator
{$1=$1} change $0 as per new OFS
1 print $0
sort -fu sort uniquely ignoring case in alphabetic order

Answer 3

Could you please try following, awk + sort solution, written and tested with shown samples. In case you want to use ignorecase then add IGNORECASE=1 in awk code.
awk '
BEGIN{
FS=" ; "
}
{
for(i=1;i<=NF;i++){
if(!a[$i]++){ print $i }
}
}
' Input_file | sort
Explanation: Adding detailed explanation for above.
awk ' ##Starting awk program from here.
BEGIN{ ##Starting BEGIN section of this program from here.
FS=" ; " ##Setting field separator as space semi-colon space here.
}
{
for(i=1;i<=NF;i++){ ##Starting a for loop till NF here for each line.
if(!a[$i]++){ print $i } ##Checking condition if current field is NOT present in array a then printing that field value here.
}
}
' Input_file | sort ##Mentioning Input_file name here and passing it to sort as Input to sort the data.