Re: Re: Hash sorting

my %calhash;
my $key = "";
my $value = "";

while (<OUTFILE>) {
    chomp;
    my ($key, $value) = split(/;/, $_);
    $calhash{$key} = $value;
}

foreach $key (sort {$b cmp $a} keys %calhash) {
    print TESTFILE "$key;$calhash{$key}\n";
}
[download]

Thank you!!!! That worked!!! Why was the chomp placed before the split?
On this line $calhash{$key} = $value what is that saying?
Just trying to learn why I was off and my logic for it. Once again, thank you!
Ben

Comment on Re: Re: Hash sorting Select or Download Code

Replies are listed 'Best First'.
Re: Re: Re: Hash sorting by rdfield (Priest) on Mar 15, 2002 at 16:32 UTC
(1) the chomp was placed before the split so that the value being split didn't have a newline. With the chomp afterwards, you're removing in the newline from $_, not $value (which was populated before the chomp) (2) in your orginal code the statement read "put the value of $key into hash at key '$key'", rather than as the updated code has it. "put the value of $value into the hash at key '$key'. rdfield	[reply]
Re: Re: Re: Hash sorting by buckaduck (Chaplain) on Mar 15, 2002 at 16:53 UTC
1. The chomp comes before the split so that you remove carriage-returns from each line before you split it into $key and $value. If you don't do this, each $value will retain a trailing carriage return. Chomping the line after the split is pointless in this case, since you don't use the implicit variable `$_` again. 2. `$calhash{$key}` is the value in `%calhash` which the key `$key` points to. I'm assigning it a new value `$value`. Later, if I want the key and value again (like in the printing loop), I'll refer to `$key` and `$calhash{$key}`. The syntax for Variable Names is covered in perldata of the perl documentation. buckaduck	[reply] [d/l] [select]