Beefy Boxes and Bandwidth Generously Provided by pair Networks
Think about Loose Coupling
 
PerlMonks  

Re: Decimal Array range

by bart (Canon)
on Dec 21, 2010 at 13:02 UTC ( #878245=note: print w/ replies, xml ) Need Help??


in reply to Decimal Array range

Perl's .. operator can do magic increments, but only for strings in the format /^[a-z]*[0-9]*$/i. But the problem you face here is that your increments must be by 1; not 1/100, not 5 minutes or 1 hour or whatever.

You'll have to somehow produce a range where increments are one, and scale them.

Plenty of people showed you how to do that with increments of 1/100, and here's a way to increment using time (in this exampel: increment in 5 minute intervals):

use POSIX qw(strftime); use Time::Local; my($from, $to, $incr) = ('13:00', '23:00', '0:05'); foreach($from, $to, $incr) { if(/^(\d+):(\d\d)(?::(\d\d))?$/) { $_ = ($1 * 60 + $2) * 60 + ($3 || 0); } } @range = map { strftime "%H:%M:%S", gmtime $_ } map $_*$incr, $from/$incr .. $to/$incr; $_ = join " ", @range; s/(.{1,70})(\s|$)/$1\n/g; print ;
Output:
13:00:00 13:05:00 13:10:00 13:15:00 13:20:00 13:25:00 13:30:00 13:35:00 13:40:00 13:45:00 13:50:00 13:55:00 14:00:00 14:05:00 14:10:00 14:15:00 14:20:00 14:25:00 14:30:00 14:35:00 14:40:00 14:45:00 14:50:00 14:55:00 15:00:00 15:05:00 15:10:00 15:15:00 15:20:00 15:25:00 15:30:00 15:35:00 15:40:00 15:45:00 15:50:00 15:55:00 16:00:00 16:05:00 16:10:00 16:15:00 16:20:00 16:25:00 16:30:00 16:35:00 16:40:00 16:45:00 16:50:00 16:55:00 17:00:00 17:05:00 17:10:00 17:15:00 17:20:00 17:25:00 17:30:00 17:35:00 17:40:00 17:45:00 17:50:00 17:55:00 18:00:00 18:05:00 18:10:00 18:15:00 18:20:00 18:25:00 18:30:00 18:35:00 18:40:00 18:45:00 18:50:00 18:55:00 19:00:00 19:05:00 19:10:00 19:15:00 19:20:00 19:25:00 19:30:00 19:35:00 19:40:00 19:45:00 19:50:00 19:55:00 20:00:00 20:05:00 20:10:00 20:15:00 20:20:00 20:25:00 20:30:00 20:35:00 20:40:00 20:45:00 20:50:00 20:55:00 21:00:00 21:05:00 21:10:00 21:15:00 21:20:00 21:25:00 21:30:00 21:35:00 21:40:00 21:45:00 21:50:00 21:55:00 22:00:00 22:05:00 22:10:00 22:15:00 22:20:00 22:25:00 22:30:00 22:35:00 22:40:00 22:45:00 22:50:00 22:55:00 23:00:00

Tweaking the format spec for strftime you can produce a different time format.


Comment on Re: Decimal Array range
Select or Download Code
Replies are listed 'Best First'.
Re^2: Decimal Array range
by Gulliver (Monk) on Dec 21, 2010 at 20:50 UTC

    I didn't realize you could assign to $_ inside a foreach loop and it will change the scalars in the list.

      In foreach, the loop variable (default $_) is an alias to the original value. That means that changing the value will change the original.
      my $x = 100; my @y = (10, 20, 30); foreach ($x, @y) { $_ *= 2; } local $" = ", "; print "\$x = $x\n\@y = (@y)\n";
      # or: foreach my $n ($x, @y) { $n *= 2; }

      Ditto in the block or expression for map and grep ($_ only).

      map { $_ *= 2 } $x, @y;
      grep { $_ *= 2 } $x, @y;

      BTW parameters to subs are aliases too, so if you change them in @_, you'll modify the originals too:

      sub double { foreach(@_) { $_ *= 2; } } double($x, @y);

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://878245]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others having an uproarious good time at the Monastery: (5)
As of 2015-07-30 11:35 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    The top three priorities of my open tasks are (in descending order of likelihood to be worked on) ...









    Results (271 votes), past polls