(jeffa) Re: Question about using hash indexes with GD::Graph

UPDATE: see comments

How about:

my (@h,@c);
push @h, $_->{hour} foreach(@{$data});   # no so great
push @c, $_->{count} foreach(@{$data});  # see extremely's comment 
my $new = [ \@h, \@c ];

$gd = $graph->plot($new);                # wrong - see orbital's comme
+nt
[download]

I really tried to avoid the temp lists, maybe someone will come along and make this puppy scream with a nasty map block. ;)

BEFORE:                          AFTER:
$VAR1 = [                        $VAR1 = [
          {                                [  
            'count' => 5,                     1,
            'hour' => 1                       5,
          },                                  2
          {                                ],
            'count' => 2,                  [
            'hour' => 5                       5,
          },                                  2,
          {                                   8
            'count' => 8,                  ]  
            'hour' => 2                  ];
          }
        ];
[download]

Data::Dumper - don't code anonymous data structures without it.

Jeff

R-R-R--R-R-R--R-R-R--R-R-R--R-R-R--
L-L--L-L--L-L--L-L--L-L--L-L--L-L--

Comment on (jeffa) Re: Question about using hash indexes with GD::Graph Select or Download Code

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Re: (jeffa) Re: Question about using hash indexes with GD::Graph by extremely (Priest) on Mar 21, 2001 at 02:43 UTC
merlyn showed ya map but honestly you shouldn't get into the habit of traipsing through a data set multiple times. When ever you see two lines that both end "`foreach (@array)`" you should be doing: `foreach (@data) { push @h, $_->{'hour'}; push @c, $_->{'count'); }` [download] You get in a hurry and do it wrong then wind up going through the same data like 7 or 8 times when there are 100,000 items in the list and you are going start wondering where your afternoon of surfing PM went. =P -- $you = new YOU; honk() if $you->love(perl)	[reply] [d/l]
Re: (jeffa) Re: Question about using hash indexes with GD::Graph by vonman (Acolyte) on Mar 20, 2001 at 21:15 UTC
This is perfect except that I had to cange the foreach lines to look like follows. `my (@h,@c); push @h, $_->{'hour'} foreach(@data); push @c, $_->{'count'} foreach(@data); my $new = [ \@h, \@c];` [download] Now it is graphing correctly	[reply] [d/l]
Re: Re: (jeffa) Re: Question about using hash indexes with GD::Graph by merlyn (Sage) on Mar 20, 2001 at 21:23 UTC
Any kind of push @x, .... for @y should immediately invoke that magic three-letter word, "m a p". `my $new = [ [map $_->{hour}, @data], [map $_->{count}, @data] ];` [download] -- Randal L. Schwartz, Perl hacker	[reply] [d/l]
(jeffa) Re: Re: Re: (jeffa) Re: Question about using hash indexes with GD::Graph by jeffa (Bishop) on Mar 20, 2001 at 21:26 UTC
Man, I was this close to getting that. Nice! Thanks once again, Randal! Jeff R-R-R--R-R-R--R-R-R--R-R-R--R-R-R-- L-L--L-L--L-L--L-L--L-L--L-L--L-L--	[reply]