Printing everything except the first field with awk

Question

I have a file that looks like this   AE  United Arab Emirates AG  Antigua  amp  Barbuda AN  Netherlands Antilles AS  American Samoa BA  Bosnia and Herzegovina BF  Burkina Faso BN  Brunei Darussalam   And I  d like to invert the order  printing first everything except  1 and then  1   United Arab Emirates AE   How can I do the  everything except field 1  trick

User · Answer

Option 1

There is a solution that works with some versions of awk:

awk '{ $(NF+1)=$1;$1="";$0=$0;} NF=NF ' infile.txt

Explanation:

       $(NF+1)=$1                          # add a new field equal to field 1.
                  $1=""                    # erase the contents of field 1.
                        $0=$0;} NF=NF      # force a re-calc of fields.
                                           # and use NF to promote a print.

Result:

United Arab Emirates AE
Antigua & Barbuda AG
Netherlands Antilles AN
American Samoa AS
Bosnia and Herzegovina BA
Burkina Faso BF
Brunei Darussalam BN

However that might fail with older versions of awk.

Option 2

awk '{ $(NF+1)=$1;$1="";sub(OFS,"");}1' infile.txt

That is:

awk '{                                      # call awk.
       $(NF+1)=$1;                          # Add one trailing field.
                  $1="";                    # Erase first field.
                        sub(OFS,"");        # remove leading OFS.
                                    }1'     # print the line.

Note that what needs to be erased is the OFS, not the FS. The line gets re-calculated when the field $1 is asigned. That changes all runs of FS to one OFS.

But even that option still fails with several delimiters, as is clearly shown by changing the OFS:

awk -v OFS=';' '{ $(NF+1)=$1;$1="";sub(OFS,"");}1' infile.txt

That line will output:

United;Arab;Emirates;AE
Antigua;&;Barbuda;AG
Netherlands;Antilles;AN
American;Samoa;AS
Bosnia;and;Herzegovina;BA
Burkina;Faso;BF
Brunei;Darussalam;BN

That reveals that runs of FS are being changed to one OFS.
The only way to avoid that is to avoid the field re-calculation.
One function that can avoid re-calc is sub.
The first field could be captured, then removed from $0 with sub, and then both re-printed.

Option 3

awk '{ a=$1;sub("[^"FS"]+["FS"]+",""); print $0, a;}' infile.txt
       a=$1                                   # capture first field.
       sub( "                                 # replace: 
             [^"FS"]+                         # A run of non-FS
                     ["FS"]+                  # followed by a run of FS.
                            " , ""            # for nothing.
                                  )           # Default to $0 (the whole line.
       print $0, a                   # Print in reverse order, with OFS.


United Arab Emirates AE
Antigua & Barbuda AG
Netherlands Antilles AN
American Samoa AS
Bosnia and Herzegovina BA
Burkina Faso BF
Brunei Darussalam BN

Even if we change the FS, the OFS and/or add more delimiters, it works.
If the input file is changed to:

AE..United....Arab....Emirates
AG..Antigua....&...Barbuda
AN..Netherlands...Antilles
AS..American...Samoa
BA..Bosnia...and...Herzegovina
BF..Burkina...Faso
BN..Brunei...Darussalam

And the command changes to:

awk -vFS='.' -vOFS=';' '{a=$1;sub("[^"FS"]+["FS"]+",""); print $0,a;}' infile.txt

The output will be (still preserving delimiters):

United....Arab....Emirates;AE
Antigua....&...Barbuda;AG
Netherlands...Antilles;AN
American...Samoa;AS
Bosnia...and...Herzegovina;BA
Burkina...Faso;BF
Brunei...Darussalam;BN

The command could be expanded to several fields, but only with modern awks and with --re-interval option active. This command on the original file:

awk -vn=2 '{a=$1;b=$2;sub("([^"FS"]+["FS"]+){"n"}","");print $0,a,b;}' infile.txt

Will output this:

Arab Emirates AE United
& Barbuda AG Antigua
Antilles AN Netherlands
Samoa AS American
and Herzegovina BA Bosnia
Faso BF Burkina
Darussalam BN Brunei

User · Answer

If you re open to a Perl solution     perl -lane  print join      F 1    F 0   file   is a simple solution with an input output separator of one space  which produces   United Arab Emirates AE Antigua  amp  Barbuda AG Netherlands Antilles AN American Samoa AS Bosnia and Herzegovina BA Burkina Faso BF Brunei Darussalam BN   This next one is slightly more complex  perl -F     -lane  print join       F 1    F 0   file   and assumes that the input output separator is two spaces   United Arab Emirates  AE Antigua  amp  Barbuda  AG Netherlands Antilles  AN American Samoa  AS Bosnia and Herzegovina  BA Burkina Faso  BF Brunei Darussalam  BN   These command-line options are used    -n loop around every line of the input file  do not automatically print every line -l removes newlines before processing  and adds them back in afterwards -a autosplit mode     split input lines into the  F array   Defaults to splitting on whitespace -F autosplit modifier  in this example splits on       two spaces  -e execute the following perl code    F is the array of words in each line  indexed starting with 0   F is the number of words in  F  F 1    F  is an array slice of element 1 through the last element  F 1    F 0  is an array slice of element 1 through the last element plus element 0

User · Answer

Yet another way         this rejoins the fields 2 thru NF with the FS and outputs one line per line of input  awk   for  i 2 i lt  NF i    printf  i  if  i  lt  NF   printf FS   printf RS     I use this with git to see what files have been modified in my working dir   git diff        grep   - -git         awk   print NF          awk -F      for  i 2 i lt  NF i    printf  i  if  i  lt  NF   printf FS   printf RS

User · Answer

awk   sub  1 FS     7  YourFile   Remove the first field and separator  and print the result  7 is a non zero value so printing  0

User · Answer

If you re open to another Perl solution   perl -ple  s    S   s       2  1   file

User · Answer

Let s move all the records to the next one and set the last one as the first     awk   a  1  for  i 2  i lt  NF  i      i-1   i   NF a 1  file United Arab Emirates AE Antigua  amp  Barbuda AG Netherlands Antilles AN American Samoa AS Bosnia and Herzegovina BA Burkina Faso BF Brunei Darussalam BN   Explanation   a  1 save the first value into a temporary variable  for  i 2  i lt  NF  i      i-1   i save the Nth field value into the  N-1 th field   NF a save the first value   1  into the last field    1 true condition to make awk perform the default action   print  0       This way  if you happen to have another field separator  the result is also good     cat c AE-United-Arab-Emirates AG-Antigua- amp -Barbuda AN-Netherlands-Antilles AS-American-Samoa BA-Bosnia-and-Herzegovina BF-Burkina-Faso BN-Brunei-Darussalam    awk  BEGIN OFS FS  -   a  1  for  i 2  i lt  NF  i      i-1   i   NF a 1  c United-Arab-Emirates-AE Antigua- amp -Barbuda-AG Netherlands-Antilles-AN American-Samoa-AS Bosnia-and-Herzegovina-BA Burkina-Faso-BF Brunei-Darussalam-BN

User · Answer

awk    saved    1   1       print substr  0  2   saved      Setting the first field to    leaves a single copy of OFS at the start of  0  Assuming that OFS is only a single character  by default  it s a single space   we can remove it with substr  0  2   Then we append the saved copy of  1

User · Answer

awk    tmp    1  sub                  print  0  tmp

User · Answer

There s a sed option too      sed  s                    2  1   inputfile txt   Explained     Swap             Match anything until we reach a space  store in  1             Match everything else  store in  2 With  2          Retrieve  2  1          Retrieve  1   More thoroughly explained     s      Swap        Beginning of source pattern        start storing this value        text not matching the space character        0 or more of the previous pattern        stop storing this value        start storing this value        any character        0 or more of the previous pattern        stop storing this value        End of source pattern  beginning of replacement  2     Retrieve the 2nd stored value  1     Retrieve the 1st stored value        end of replacement

User · Answer

Use the cut command with -f 2-  POSIX  or --complement  not POSIX     echo a b c   cut -f 2- -d     b c   echo a b c   cut -f 1 -d     a   echo a b c   cut -f 1 2 -d     a b   echo a b c   cut -f 1 -d     --complement b c

User · Answer

Assigning  1 works but it will leave a leading space  awk   first    1   1       print  0  first      You can also find the number of columns in NF and use that in a loop

User · Answer

A first stab at it seems to work for your particular case   awk    f    1  i    NF  while  i  lt   0   gsub    A-Z  A-Z              print  i  f

User · Answer

Maybe the most concise way     awk     NF 1   1  1    sub FS      infile United Arab Emirates AE Antigua  amp  Barbuda AG Netherlands Antilles AN American Samoa AS Bosnia and Herzegovina BA Burkina Faso BF Brunei Darussalam BN   Explanation     NF 1   1  Generator of a  new  last field    1     Set the original first field to null  sub FS      After the first two actions    NF 1   1  1     get rid of the first field separator by using sub  The final print is implicit

User · Answer

Another and easy way using cat command  cat filename   awk   print  2  3  4  5  6  1    gt  newfilename

User · Answer

1    leaves a space as Ben Jackson mentioned  so use a for loop   awk   for  i 2  i lt  NF  i    print  i   filename   So if your string was  one two three   the output will be   two  three  If you want the result in one row  you could do as follows   awk   for  i 2  i lt NF  i    printf  i      print  NF   filename   This will give you   two three

User · Answer

The field separator in gawk  at least  can be a string as well as a character  it can also be a regex   If your data is consistent  then this will work   awk -F        print  2  1   inputfile   That s two spaces between the double quotes

[awk] Printing everything except the first field with awk

Option 1

Option 2

Option 3

Examples related to awk

Examples related to sed