in reply to Length of multidimensional array based on the particular index value

grep in scalar context... evil? It works.

say scalar grep{ $_->[2] } @select;

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There's also 'for'

my $length;

$length++ if $_->[2] for @select;
say $length;

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Dave

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Re^2: Length of multidimensional array based on the particular index value
by Eliya (Vicar) on Feb 24, 2011 at 10:23 UTC
    $length++ if $_->[2] for @select;

    Unfortunately, Perl doesn't understand this "double modifier" syntax (syntax error at..., near "] for "), so it would have to be: 

    do { $length++ if $_->[2] } for @select;

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      it would have to be: do { $length++ if $_->[2] } for @select;

      Can also be:

      $_->[2] and $length++ for @select;

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      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.
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        And since $_->[2] is either 0 or 1 you could do: 

        $length+=$_->[2] for @select;

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      there you go taking all my fun away!

      Here's an awful contortion: 

      $_->[2]?length++:0 for @select;

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      Dave

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        $_->[2]?length++:0 for @select;

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        Why are you trying to increment the length function?

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        or even 

        $length += !!$_->[2] for @select;

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        :)

        (the !! is only required if you don't want to make assumptions that a "true" value in $_->[2] is always represented as 1)

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