Re: Delete every other value in an array
by Ara.T.Howard other posts by this author
May 9 2008 8:08AM messages near this date
Re: Delete every other value in an array
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running a script through remote desktop
On May 9, 2008, at 8:35 AM, yermej wrote:
> a = %w(a b c d e f g h i j k)
> 1.upto(a.size) {|i| a.delete_at i}
it does, but accidentally:
cfp:~ > cat a.rb
a = %w(a b c d e f g h i j k)
1.upto(a.size) do |i|
puts '---'
p :i => i
p :before => a
a.delete_at i
p :after => a
end
cfp:~ > ruby a.rb
---
{:i=> 1}
{:before=> ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k"]}
{:after=> ["a", "c", "d", "e", "f", "g", "h", "i", "j", "k"]}
---
{:i=> 2}
{:before=> ["a", "c", "d", "e", "f", "g", "h", "i", "j", "k"]}
{:after=> ["a", "c", "e", "f", "g", "h", "i", "j", "k"]}
---
{:i=> 3}
{:before=> ["a", "c", "e", "f", "g", "h", "i", "j", "k"]}
{:after=> ["a", "c", "e", "g", "h", "i", "j", "k"]}
---
{:i=> 4}
{:before=> ["a", "c", "e", "g", "h", "i", "j", "k"]}
{:after=> ["a", "c", "e", "g", "i", "j", "k"]}
---
{:i=> 5}
{:before=> ["a", "c", "e", "g", "i", "j", "k"]}
{:after=> ["a", "c", "e", "g", "i", "k"]}
---
{:i=> 6}
{:before=> ["a", "c", "e", "g", "i", "k"]}
{:after=> ["a", "c", "e", "g", "i", "k"]}
---
{:i=> 7}
{:before=> ["a", "c", "e", "g", "i", "k"]}
{:after=> ["a", "c", "e", "g", "i", "k"]}
---
{:i=> 8}
{:before=> ["a", "c", "e", "g", "i", "k"]}
{:after=> ["a", "c", "e", "g", "i", "k"]}
---
{:i=> 9}
{:before=> ["a", "c", "e", "g", "i", "k"]}
{:after=> ["a", "c", "e", "g", "i", "k"]}
---
{:i=> 10}
{:before=> ["a", "c", "e", "g", "i", "k"]}
{:after=> ["a", "c", "e", "g", "i", "k"]}
---
{:i=> 11}
{:before=> ["a", "c", "e", "g", "i", "k"]}
{:after=> ["a", "c", "e", "g", "i", "k"]}
look carefully at what's happening for i > = 6.
the indexes map only by accident since each delete modifies the
mapping in the array (size reduced by one after each delete)
a @ http://codeforpeople.com/
--
we can deny everything, except that we have the possibility of being
better. simply reflect on that.
h.h. the 14th dalai lama
Thread:
Tim Conner
7stud --
S2
David A. Black
7stud --
Joel VanderWerf
Yermej
Robert Dober
Robert Dober
Ara.T.Howard
James Gray
rgs
Ara.T.Howard
Harry Kakueki
Harry Kakueki
Harry Kakueki
Yermej
Ara.T.Howard
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