OT: a problem about text manipulation

[Paul Smith]

On 10/31/06, Hirofumi Saito <hi_saito at yk.rim.or.jp> 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,

Paul