What is the efficiency and quality of this shuffling algorithm?

Question

This recent question about random sorting using C # made me wonder how I sometimes shuffled my arrays in Perl.

@shuffled = sort { rand() <=> rand() } @array;

Proposed solution to this issue of Fisher-Yates shuffle , which runs for linear time.

Question: How effective is my fragment and such a random random random case?

Answer 1

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Answer 2

$ perldoc List::Util
⋮
  shuffle LIST
       Returns the elements of LIST in a random order

           @cards = shuffle 0..51      # 0..51 in a random order
⋮

.

Answer 3

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Answer 4

perl sort

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ETA: . 100000 FY-shuffle 10 .

Answer 5

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Answer 6

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Answer 7

There is the best Fisher-Yates Shuffle feature that doesn't use the sortbuilt-in perlfaq4: how do I randomly shuffle an array? .

Answer 8

@shuffled = map {
  $_->[1]
} sort {
  $a->[0] <=> $b->[0]
} map {
  [ rand(), $_ ]
} @array;