Beefy Boxes and Bandwidth Generously Provided by pair Networks
Problems? Is your data what you think it is?
 
PerlMonks  

Re: Rosetta code: Split an array into chunks

by moritz (Cardinal)
on Sep 25, 2010 at 10:15 UTC ( #861941=note: print w/replies, xml ) Need Help??


in reply to Rosetta code: Split an array into chunks

Here is a Perl 6 solution in a single statement. It's probably not the best solution, but it does work today in rakudo:
my @l = <a bb c d e f g h>; sub chunky(@l, $len) { (0, $len ...^ *>=@l).map({@l[$_ .. ($_ + $len - 1 min @l.end)] ~ " +\n" }).join } print chunky(@l, 3);

The 0, $len ...^ *>=@l creates a list in steps of $len, up to (but excluding) the number of elements in @l.

Inside the map there is an array slice. The min @l.end is only necessary because Rakudo doesn't clip array slices to the end of the list yet (which is a known and reported bug).

I'm still looking for a nicer solution, will update my post if I find one.

Update: Nicer solution:

my @l = <a bb c d e f g h>; sub chunky(@l, $len) { (@l Z (' ' xx $len - 1, "\n") xx *).join.substr(0, -1) ~ "\n"; } print chunky(@l, 3);

This creates an infinite list (' ', ' ', "\n", ' ', ' ', "\n", ...), and then zips the input list with it. (zip = takes one item from each list in turn). Zips stops when the shortest list is exhausted, so we don't have to worry about it looping forever.

The result is then joined together, and the last separator is unconditionally substituted for a newline.

Perl 6 - links to (nearly) everything that is Perl 6.

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://861941]
help
Chatterbox?
choroba's discovered two instances of a weird animal in the code at work: \@$var
[Eily]: hum, tied scalar, generates a new array when derefed ? :D

How do I use this? | Other CB clients
Other Users?
Others drinking their drinks and smoking their pipes about the Monastery: (8)
As of 2017-09-26 08:41 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?
    During the recent solar eclipse, I:









    Results (293 votes). Check out past polls.

    Notices?