Hello Monks,
I am having a problem shuffling each of the sub-arrays within an array-of-arrays. I'm using the Fisher-Yates shuffle algorithm, as found in 'perldoc -q shuffle'; but I can't get it to work. I've tried three approaches, one using an array of strings, another using an array of array references, and the last using a two dimensional array. None of them work, and I'm not sure why; they just print the contents of the array in the original (unshuffled) order. Can anyone give me some tips?
Thanks in advance!

Rod
my @weeks = ('@week01','@week02','@week03');
my @weeks_refs = ("\@week01","\@week02","\@week03");
my @weeks_arr = ([0..13],[0..11],[0..11]);
my @week01 = (0..13);
my @week02 = (0..11);
my @week03 = (0..11);

for my $ref (@weeks) {
   for ($i = @$ref; --$i;) {
      my $r = int rand ($i+1);
      @$ref[$i, $r] = @$ref[$r, $i];
   }
}
for(@weeks){
   print;
}

for my $ref (@weeks_refs) {
   for ($i = @$ref; --$i;) {
      my $r = int rand ($i+1);
      @$ref[$i, $r] = @$ref[$r, $i];
   }
}
for(@weeks_refs){
   print;
}

for my $ref (@weeks_arr) {
   for ($i = @$ref; --$i;) {
      my $r = int rand ($i+1);
      @$ref[$i, $r] = @$ref[$r, $i];
   }
}
for(@weeks_arr){
   print;
}

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In reply to How to Shuffle Multidimensional Arrays? by Withigo

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