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|
$ echo 'foo bar' | awk '{ print }'
foo bar
$ echo 'foo bar' | awk '{ print $0 }'
foo bar
$ echo 'foo bar' | awk '{ print $1 }'
foo
$ echo 'foo bar' | awk '{ print $2 }'
foo
$ echo 'foo
bar' | awk '{ print $1 }'
foo
bar
$ # concat using commas to concat with spaces
$ echo '1 2 3
4 5 6' | awk '{ print $1,$2 }'
1 2
4 5
$ # concat with content
$ echo '1 2 3
4 5 6' | awk '{ print $1 "," $2 }'
1,2
4,5
$ # NF == number of fields == last column
$ echo '1 2 3
4 5 6' \
| awk '{ print $NF }'
3
6
$ # -F: flag to set the field separator, default space
$ echo 'foo bar,popo tutu' | awk -F',' '{ print $2 }'
popo tutu
$ # working
$ echo 'id,first name,last name
1,foo,bar
2,Patrick,Dupont
3,Chuck,Noris' | awk -F',' '{ print $NF "\t" $(NF-1) }'
last name first name
bar foo
Dupont Patrick
Noris Chuck
$ # NR == number of rows
$ echo 'foo bar
one two' | awk '{ print NR " " $2 }'
1 bar
2 two
$ # regexp
$ echo 'foo poo
foobar hello' | awk '/bar/ { print $2 }'
hello
$ # match field
$ echo 'foo bar
popo titi' | awk '$2 == "titi" { print $1 }'
popo
$ # match within specific field
$ echo 'foobar popo
titi tutu' | awk '$1~/ba/ { print $2 }'
popo
$ # printf with substr (index starts from 1)
$ echo 'somelongstring
anotherlongstring' | awk '{ printf "%s\n", substr($1,1,5) }'
somel
anoth
$ # using %-Ns to set the desired column with
$ echo 'id,first name,last name
1,foo,bar
2,Patrick,Dupont
3,Chuck,Noris' | awk -F',' '{ printf "%-20s \t %-10s \t %s \n", NR, $2, $3 }'
1 first name last name
2 foo bar
3 Patrick Dupont
4 Chuck Noris
$ # AWK BEGIN END
$ echo '1,foo
2,bar
3,foobar' | awk -F',' '
BEGIN { print "computing average..." }
{ total = total + $1 }
END { print "average is:", total/NR }'
computing average...
average is: 2
|
