Re: Processing a file into smaller chunks

[Stephane CHAZELAS]

2010-03-11, 04:10(-08), Javier Montoya:
[...]
> I'm a newbie with bash programming and I'm trying to process a file
> into smaller
> chunks. Let's say I've to process the file below ('X' and 'Y' are any
> possible float number):
>
> 0 0 0 0 0 0
> 0 0 0 0 0 0
> X X X X X 1.70
> 0 0 0 0 0 0
> X X X X X 1.60
> 0 0 0 0 0 0
> X X X X X 1.30
> Y Y Y Y Y 1.90
> 0 0 0 0 0 0
> 0 0 0 0 0 0
> X X X X X 2.10
>
> The lines containing 0’s can be thought as being delimiters. I need to
> find between the delimiters, which line has the highest value in the
> last column (column#6), and, just output the corresponding line. Does
> anybody could shed some light on it? An example of the desired output
> would be:
>
> X X X X X 1.70
> X X X X X 1.60
> Y Y Y Y Y 1.90
> X X X X X 2.10
>
> Is it possible to obtain such a result using bash scripting?
[...]

Yes, you don't even need the syntax of your script to be
bash-specific:

awk '
  function end_block() {
    if (max) print max_line
    max=0
  }
  $NF == 0 {
    end_block()
    next
  }
  $NF > max || !max {
    max=$NF
    max_line=$0
  }
  END {end_block()}' < the-file

Should work with any shell of the Bourne (including bash or any
standard Unix shell) or rc families.

-- 
Stéphane