Re: Better way?

If you are looking to do specifically what you state in your first sentence (assuming your print statements are for debugging purposes), you can do something like:

my @new = qw(4 5 6 7);
my %old = qw(1 a 2 b 3 c 4 d 5 f);

my %new;
$new{$_} = $old{$_} for @new;
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   MeowChow                                   
               s aamecha.s a..a\u$&owag.print

Comment on Re: Better way? Download Code

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(dkubb) Re: (2) Better way? by dkubb (Deacon) on Feb 16, 2001 at 11:50 UTC
MeowChow, here's another version using a hash slice instead of a for loop to assign the contents of one hash to another: `my %old = ( 1 => a, 2 => b, 3 => c, 4 => d, 5 => f, ); my @keys = qw(4 5 6 7); #Keys to copy from the old to the new hash my %new; @new{ @keys } = @old{ @keys };` [download] In this case, the difference between using a for loop and a hash slice means a slight edge in speed during benchmarking. However, the larger the data set the wider the gap becomes.	[reply] [d/l]

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(dkubb) Re: (2) Better way?
by dkubb (Deacon) on Feb 16, 2001 at 11:50 UTC

MeowChow, here's another version using a hash slice instead of a for loop to assign the contents of one hash to another:

my %old = (
  1 => a,
  2 => b,
  3 => c,
  4 => d,
  5 => f,
);

my @keys = qw(4 5 6 7);  #Keys to copy from the old to the new hash

my %new;
@new{ @keys } = @old{ @keys };
[download]

In this case, the difference between using a for loop and a hash slice means a slight edge in speed during benchmarking. However, the larger the data set the wider the gap becomes.

[reply]
[d/l]