in reply to Where is my foreach data going to?

OK, here's a reply to my own post. But it should reveal why I don't think it's a problem with data types. This will trim out some of the debugging code, but what you'll see it that only an occasional assignment is not made: 
@row is assigned 31 Medium Orange carb 14 2 0.2
@athlete[$i,$j] is assigned the value
@athlete[$i,$j] is assigned the value Medium Orange
@athlete[$i,$j] is assigned the value carb
@athlete[$i,$j] is assigned the value 14
@athlete[$i,$j] is assigned the value 2
@athlete[$i,$j] is assigned the value 0.2
@row is assigned 42 1/2 c. (cooked) past carb 19.5 3.2 0.4
@athlete[$i,$j] is assigned the value 42 42
@athlete[$i,$j] is assigned the value
@athlete[$i,$j] is assigned the value carb
@athlete[$i,$j] is assigned the value 19.5
@athlete[$i,$j] is assigned the value 3.2
@athlete[$i,$j] is assigned the value 0.4
@row is assigned 26 1/2 c. canned peache carb 14 1 0
@athlete[$i,$j] is assigned the value 26 0.4
@athlete[$i,$j] is assigned the value 1/2 c. canned peache 1/2 c. cann
+ed peache
@athlete[$i,$j] is assigned the value
@athlete[$i,$j] is assigned the value 14
@athlete[$i,$j] is assigned the value 1
@athlete[$i,$j] is assigned the value 0
@row is assigned 6 White Bread III carb 24.5 4.1 2.3
@athlete[$i,$j] is assigned the value 6
@athlete[$i,$j] is assigned the value White Bread III 0
@athlete[$i,$j] is assigned the value carb carb
@athlete[$i,$j] is assigned the value
@athlete[$i,$j] is assigned the value 4.1
@athlete[$i,$j] is assigned the value 2.3
@row is assigned 20 Marias Spanish Rice carb 42.4 4.3 5
@athlete[$i,$j] is assigned the value 20
@athlete[$i,$j] is assigned the value Marias Spanish Rice
@athlete[$i,$j] is assigned the value carb 2.3
@athlete[$i,$j] is assigned the value 42.4 42.4
@athlete[$i,$j] is assigned the value
@athlete[$i,$j] is assigned the value 5

[download]
See what I mean? It just seems to almost be caching or writing out of order. I'm sure it's my mistake, but I sure don't know why it's doing this. These are the results from my original code base.

Replies are listed 'Best First'.
Re: Re: Where is my foreach data going to?
by Roger (Parson) on Sep 18, 2003 at 02:03 UTC
    It has everything to do with data types! @athelete[$i,$j], $athelete[$i, $j] and $athelete[$i][$j] are completely different. Try to use the Data::Dumper to investigate why: 
    use strict;
use Data::Dumper;

my @array;

for (my $i=0;$i<2;$i++)
{
  for (my $j=0;$j<2;$j++)
  {
     @array[$i, $j] = "$i.$j";
  }
}
print "Case 1...\n";
print Dumper(@array);

for (my $i=0;$i<2;$i++)
{
  for (my $j=0;$j<2;$j++)
  {
     $array[$i][$j] = "$i . $j";
  }
}
print "Case 2...\n";
print Dumper(@array);

for (my $i=0;$i<2;$i++)
{
  for (my $j=0;$j<2;$j++)
  {
     $array[$i, $j] = "$i . $j";
  }
}
print "Case 3...\n";
print Dumper(@array);

    [download]
    You will get - 
    Case 1...
$VAR1 = undef;
$VAR2 = undef;
Case 2...
$VAR1 = [
          '0 . 0',
          '0 . 1'
        ];
$VAR2 = [
          '1 . 0',
          '1 . 1'
        ];
Case 3...
$VAR1 = '1 . 0';
$VAR2 = '1 . 1';

    [download]
    As you can see, only case 2 gives you what you want, a two dimensional array.
[reply]
[d/l]
[select]
      Just one point , when using Data::Dumper::Dumper() to dump an array or a hash, it is often better to pass a reference to the hash/array, as the output looks more like the original data structure - and you avoid the copying overhead of call-by-value vs call-by-refernce 
      use Data::Dumper;
my @array = (1,2,3,4,5,6,7);
print Dumper(\@array);
my %hash;
# below is a hash slice - you should learn about these
@hash{@array} = @array;# a hash whose keys == its values
print Dumper(\%hash);

      [download]
      results in the output 
      $VAR1 = [
          1,
          2,
          3,
          4,
          5,
          6,
          7
        ];
$VAR1 = {
          '7' => 7,
          '1' => 1,
          '2' => 2,
          '3' => 3,
          '4' => 4,
          '5' => 5,
          '6' => 6
        };

      [download]
      which to my eyes seems nicer
[reply]
[d/l]
[select]

        which to my eyes seems nicer

        And more accurate too. If the data structure was complex then the end result would be extremely confusing. Especially with Purity(1).


        ---
        demerphq

        <Elian> And I do take a kind of perverse pleasure in having an OO assembly language...
[reply]
[d/l]

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