Concatenating multiple lines after pattern match

Question

I have a file with data as follows:

STUDENT DETAILS
NAME MARKS STD
XYZ 20 I
RANK SCHOOL TEACHER GRADE
5 TTT ANON B
POSITION
5
STUDENT DETAILS
NAME MARKS STD
ABC              40                I
RANK SCHOOL TEACHER GRADE
5 TTT ANON A
POSITION
5

I want my output as:

NAME MARKS STD RANK SCHOOL TEACHER GRADE POSITION
XYZ  20     I   5    TTT   ANON    B     5
ABC  40     I   5    TTT   ANON    A     5

I have tried finding the pattern STUDENT DETAILS through awk and printing 2nd, 5th and 8th lines after that. But the line needs to be concatenated.

I ran:

awk '/STUDENT DETAILS/{nr[NR];nr[NR+2]; nr[NR+5]; nr[NR+8]}; END {for (i in nr) print nr[i]}' file.txt > filenew.txt

How can I achieve this?

Answer 1

awk '
    BEGIN { OFS="\t"; maxLines=7 }
    { lineNr=(NR-1) % maxLines + 1; $1=$1; lines[lineNr]=$0 }
    NR == maxLines     { print lines[2], lines[4], lines[6] }
    lineNr == maxLines { print lines[3], lines[5], lines[7] }
' file
NAME    MARKS   STD     RANK    SCHOOL  TEACHER GRADE   POSITION
XYZ     20      I       5       TTT     ANON    B       5
ABC     40      I       5       TTT     ANON    A       5

Answer 2

you can't read ahead in awk, you have to remember pattern

awk file (u.awk below)

/STUDENT/ { li=NR;}
NR == li+2 { mark[li]=$0 }
NR == li+4 { pos[li]=$0 }
END { for (m in mark) printf "%s %s\n",mark[m],pos[m] ;}

where

• /STUDENT/ { li=NR;} remember line where record start
• NR == li+2 { mark[li]=$0 } when current line is +2, remember mark (likewise for position)

when run with you sample data (I delete empty lines, adjust +2/+4 if present on actual file), this give

awk -f u.awk liste-1.txt

XYZ 20 I 5 TTT ANON B
ABC              40                I 5 TTT ANON A

generation of header omited.

Answer 3

If you pre-split the data into records, you can get away with printing the relevant fields:

# Pre-splitting
sed '/^STUDENT/ { 1!s/^/\n/; }' infile |

# Reorder the record:
awk -v RS= -v FS='\n' '
  NR == 1 { print $2, $4, $6 }
          { print $3, $5, $7 }'        |

# Pretty-print columns
column -t

Output:

NAME  MARKS  STD  RANK  SCHOOL  TEACHER  GRADE  POSITION
XYZ   20     I    5     TTT     ANON     B      5
ABC   40     I    5     TTT     ANON     A      5

Answer 4

Gnu sed constructs and extended regex mode enabled:

 $ sed -nEe '
      1,6{
         N;7!s/^/\n/;7!D;h





  s/(.*)\n(.*)\n(.*)\n(.*)\n(.*)\n(.*)\n(.*)/\2\t\4\t\6/p
         ba
     }
    /STUDENT/!{H;$!d;:a;g;}

      s/(.*)\n(.*)\n(.*)\n(.*)\n(.*)\n(.*)\n(.*)/\3\t\5\t\7/p
 ' file.txt


 NAME   MARKS   STD RANK    SCHOOL  TEACHER GRADE   POSITION
 XYZ    20  I   5   TTT ANON    B   5
 ABC    40  I   5   TTT ANON    A   5

Answer 5

Tested with below script and it worked fine


STEP1:

header=`sed '/STUDENT/d' r.txt |sed -n '1~2p'| sort | uniq| sed "N;s/\n/ /g"| sed "N;s/\n/ /g"`

count=`sed '/STUDENT/d'  o.txt|wc -l`
sed -i '/STUDENT/d' o.txt

STEP2:
for ((i=1;i<=$count;i++)); do j=$(($i+5)); sed -n ""$i","$j"p" o.txt| sed -n '2~2p'|sed -r "s/\s+/ /g"|sed "N;s/\n/ /g"|sed "N;s/\n/ /g"; i=$j; done| awk -v header="$header" 'BEGIN{print header}{print $0}'| sed "s/ /\t/g"