linux get specific fields from several files

I have several files starting with the string “file” then a number (file1, file2, etc).

The content of these files is similar and looks like this

file1:
$xx_ at 10.0 "$elt_(0) coordinates 636.46 1800.37 9.90"
$xx_ at 10.0 "$elt_(1) coordinates 367.78 1263.63 7.90"

For each file, I want only keep the index of the element and the 2 numeric fields just after coordinates (in the same file or in another file):

file1:

0  636.46 1800.37 
1 367.78 1263.63 

What I tried to do is like this (but It is not correct)

find . -name "file*"|while read fname; do
  echo "$fname"
  for line in $(cat "$fname") do
   FS="[_() ]"
   print   $7 "t" $10 "t" $11 > $fname
  done
done

Answer

This is the perfect use of awk. With awk you can simply print specific words.

If the index is the line number you can use this:

cat -n ./file1 | awk '{print $1 -1 " " $7 " " $8}' this simply prints the files with line numbers and prints the first, seventh and eighth word.

If the index is the $elt_(0) number in parenthese you can use sed like this:

cat ./file1 | awk '{print $4 " " $7 " " $8}' | sed 's/"$elt_(//g' | sed 's/)//g' | sed 's/"//g'

output:

1 636.46 1800.37
2 367.78 1263.63

Link to awk Link to sed