Hi, I'm trying to create an array of indicies got by sorting another array,
e.g if my array is @list = (4,9,3) then the array of indicies should be
(2,0,1). This question is already in the Q&A and the solution provided
by Merlyn is 

    my @indicies = sort { $a[$a] <=> $a[$b] } 0..$#list;

[download]
however I keep getting the message
Use of uninitialized value in numeric comparison (<=>) at test.pl
and indicies = (0,1,2), I'm rightly stumped by this and any help
greatly appreciated.
Thanks Damian 
#!/usr/local/bin/perl -w
  @list = (4,9,3);
  my @indicies = sort { $a[$a] <=> $a[$b] } 0..$#list;
  print ("\n @indicies");

[download]

In reply to sorting and indicies by Anonymous Monk

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