OT: a problem about text manipulation

[Paul Smith]

On 11/4/06, Les Mikesell <lesmikesell at gmail.com> wrote:
> > > > >I am looking for an automatic way of transforming my text file into
> > > > >another one with the format
> > > > You may try this:
> > > >  cat ./test.txt | awk '{print $1" "$2; print $1" "$3; print $1" "$4}' |
> > > >  grep -v ' $'
> > >
> > > $ awk '{for(i=2;i<=NF;i++)printf $1"\t"$i"\n"}' test.txt
> > >
> > > That's all.
> > >
> > > or, try this.
> > >
> > > $ awk '{for(i=2;i<=NF;i++)print $1, $i}' test.txt
> > >
> > > I think awk is the best solution for this problem.
> >
> > The following command does almost exactly what I want:
> >
> > cat ./filename_introduced_user.txt | awk '{print $1" "$2; print $1"
> > "$3; print $1" "$4; print $1" "$5; print $1" "$6; print $1" "$7; print
> > $1" "$8; print $1" "$9; print $1" "$10; print $1" "$11; print $1"
> > "$12; print $1" "$13; print $1" "$14; print $1" "$15; print $1" "$16;
> > print $1" "$17; print $1" "$18; print $1" "$19; print $1" "$20; print
> > $1" "$21; print $1" "$22; print $1" "$23; print $1" "$24; print $1"
> > "$25; print $1" "$26; print $1" "$27}' | grep -v ' $' >
> > another_filename_introduced_user.txt
> >
> > I am wondering whether it is possible to write a script to do the same
> > but for a number of columns introduced by the user.
> >
> > Thanks in advance,
>
> If you want to adapt to the columns in the file, this
> would work:
>
> #!/bin/sh
> while read LINE
> do
>  set -- $LINE
>  N=$1
>  while shift
>  do
>   if [ -n "$1" ]
>   then
>    echo $N $1
>    fi
>  done
> done
>                                                                                 If you want to set a limit on the columns you could add a
> counter on the loop doing the shift and pass a value in
> on the command line.

Thanks, Les. I have meanwhile learned a bit of Ruby and I could do the
same with it.

Paul