use strict;
use warnings;
my ( $cmd, $err );

my ( @Counter, @Tot );
my ( $time, $interval, $n_elements, @data )
  = split(/,/, scalar <DATA>);

my $start = my $seconds = time;
for my $data ( @data ) {
  my $value;
  $seconds += $interval;
  if ( $interval == 60 ) {
    $value = sprintf("%0.2f", $data/1000);
  }
  else {
    $value = sprintf("%0.2f", ($data*8)/1000);
  }
  my $bin = int( ( $seconds-$start )/300 );
  $Counter[ $bin ]++;
  $Tot[ $bin ] += $value;
  # etc.
}

use POSIX 'strftime';
my $t = int( $start/300 )*300;
for my $i ( 0..$#Counter ) {
  my $timestring =
    strftime( "%m/%d/%y.%H:%M:%S", localtime( $t ) );
  print join("\t", $timestring, $Counter[ $i ], $Tot[ $i ]), $/;
  $t += 300;
}
__DATA__
07:30:04,60,750,32058,41,98,41,41,98,43,41,73,98,18050,467,428,260,363,836,258,1499,247,489,1208,469,633,749,439,342,258,706,817,639,2174,848,909,557,876,1633,1116,1090,665,1150,817,1592,791,1741,935,675,2370,2039,2121,911,1955,1526,608,656,375,1488,529,376,268,1082,1858,2036,1282,859,1356,1654,1620,2074,1546,488,2999,1564,1509,811,1427,2149,611,1548,803,2313,1823,1575,1733,1168,2511,1034,2090,1491,2361,2663,2062,1455,957,3549,3097,2443,2680,2262,2152,2176,2645,3029,2078,1395,1961,801,1955,1395,1465,1030,976,1026,813,932,1745,450,1172,1457
__END__
04/28/05.18:20:00       4       32.24
04/28/05.18:25:00       5       0.29
04/28/05.18:30:00       5       19.31
04/28/05.18:35:00       5       3.21
04/28/05.18:40:00       5       3.55
04/28/05.18:45:00       5       2.57
04/28/05.18:50:00       5       5.13
04/28/05.18:55:00       5       5.39
04/28/05.19:00:00       5       6.09
04/28/05.19:05:00       5       8.15
04/28/05.19:10:00       5       5.67
04/28/05.19:15:00       5       3.05
04/28/05.19:20:00       5       7.12
04/28/05.19:25:00       5       8.25
04/28/05.19:30:00       5       7.37
04/28/05.19:35:00       5       6.54
04/28/05.19:40:00       5       8.6
04/28/05.19:45:00       5       9.48
04/28/05.19:50:00       5       10.69
04/28/05.19:55:00       5       12.63