http://qs321.pair.com?node_id=1107617


in reply to take 'n' array elements at a time

Doesn't sound too demanding computationally. Create a routine that reads n number of records from a given file, adding all the values and dividing by n. Then run it for every file you're interested in.

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Re^2: take 'n' array elements at a time
by fionbarr (Friar) on Nov 18, 2014 at 20:07 UTC
    here's what I think I'll use: (the entire file is in @array) 
    my @i;

while (@array) {
        last if (scalar @array < 9);
        push @i, shift @array for 0 .. 8;
        print join ("\n", @i);
        print "\n------------------------------------------\n";
        @i = ();
        }

    [download]
    Thanks
[reply]
[d/l]

      Hi,

      Well that code is a step in the right direction. Couple things though, you can put the test inside the while loop instead of using "last". You can grab the first 9 items off of the array and delete them from the array in one operation using splice. This lets you avoid using the "@i" array. So:

      my @array = map {$_ * 10} 1 .. 20;   # test data
while (@array > 8) {
        print join "\n", splice(@array,0,9);
        print "\n--------------------\n";
}

      [download]

      Note that if the array isn't divisible by 9, the last few items will be silently ignored. If you'd rather see them, it's safe to just omit the "> 8".. splice will return whatever remains even though it's not the full 9 items.

[reply]
[d/l]
        lovely! adding 'splice' to my lexicon thanks
[reply]

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