On Jul 2, 9:20 am, [EMAIL PROTECTED] wrote:
> i had a problem with hashes...can any one help
>
> ihad a hash with keys and values...
>
> # DEFINE A HASH
> %coins = ( "12345" , 91,
> "987658" ,35.5,
> "wer123", 99.8,
> "456hn",56.4,
> "34567",78.9,
> "00000",99.9,
> "yui345",45.4);
>
> # LOOP THROUGH IT
> foreach $value (sort {$coins{$a} cmp $coins{$b} } keys %coins)
You're iterating through a sorted list of keys, but you're calling
each one of those keys "$value". That's bound to confuse a future
reader of your code (which may end up being yourself)
> {
> print "<$value---> $coins{$value}>\n";
>
> }
>
> so now is hash is printing in sorted order....like
> <987658---> 35.5>
> <yui345---> 45.4>
> <456hn---> 56.4>
> <34567---> 78.9>
> <12345---> 91>
> <wer123---> 99.8>
> <00000---> 99.9>
>
> wat i need is for ex if i gave 34567 it has to tell the position of
> the hash 4th position...
You're asking for Perl to tell you something that's not true. 34567
is NOT at the "fourth position". It's not at any such numbered
position. 34567 is a key whose value in %coins is 78.9.
> how can i do that.....
Sounds to me like what you really want is to get a list of keys in
some particular order (like the one you imposed in your foreach loop
above), find the position of one particular key in the sorted list of
keys. That's not the same thing as finding the position of one
particular key in the hash itself. Here's one way:
my $i = 0;
foreach my $key (sort {$coins{$a} cmp $coins{$b} } keys %coins)
{
$i++;
print "$key is at position $i\n" if $key eq '34567';
}
Here's another:
my $i = 0;
my %position_of = map { $_ => ++$i } sort {$coins{$a} cmp $coins{$b} }
keys %coins;
print "Position of '34567' is $position_of {34567}\n";
Hope this helps,
Paul Lalli
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