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Re: raw data formatting

by roboticus (Chancellor)
on Nov 16, 2012 at 00:24 UTC ( #1004086=note: print w/replies, xml ) Need Help??

in reply to raw data formatting


Part of the difficulty appears to be that the file may have some lines you want to discard. Since the $. variable keeps track of the lines read and not the lines wanted, using the modulo operator on it is going to fail. However, the modulo operator idea is a *good* one, you just need to keep track of the lines you want to keep yourself:

my $cnt_keepers=0; while (my $ln = <$f>) { next if .... # Now we've got a line we want to keep ++$cnt_keepers; if ($cnt_keepers % 5 == 0) { ... every fifth line processing ... } ... }

Another way you could do it is to simply accumulate the lines you want, and when you have five, process the lot of 'em:

my @records; while (my $ln = <$f>) { next if ... push @records, $ln; if (@records==5) { print "A $records[0]\n"; print "B $records[1]\n"; print "C $records[2]\n"; print "D $records[3]\n"; print "E $records[4]\n"; print "F $records[5]\n"; @records = (); } }

It may be coincidence, but it seems like the first record of each group always has a 'Z' (?record type indicator?) around column 20. If it's not a coincidence, then another way to handle it would be to accumulate records until you find a line with a 'Z' marker, then process all the records you have, and then put the new record into the accumulator.

Update: Fixed a code tag.


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