[#389739] Ruby Challenge — teresa nuagen <unguyen90@...>

Here is a ruby challenge for all you computer science lovers out there,

22 messages 2011/11/05
[#389769] Re: Ruby Challenge — "Jonan S." <jonanscheffler@...> 2011/11/05

Totally unrelated to any husker computer science programs right? Like

[#389905] Re: Ruby Challenge — Stephen Ramsay <sramsay.unl@...> 2011/11/09

Jonan S. wrote in post #1030330:

[#389907] Re: Ruby Challenge — aseret nuagen <unguyen90@...> 2011/11/09

> You mean like the professor for the course? Because that would be me .

[#389915] Re: Ruby Challenge — Robert Klemme <shortcutter@...> 2011/11/09

On Wed, Nov 9, 2011 at 4:52 AM, aseret nuagen <unguyen90@aim.com> wrote:

[#389792] Tricky DSL, how to do it? — Intransition <transfire@...>

I'd want to write a DSL such that a surface method_missing catches

18 messages 2011/11/06

[#389858] Compiling Ruby Inline C code - resolving errors — Martin Hansen <mail@...>

I am trying to get this Ruby inline C code http://pastie.org/2825882 to

12 messages 2011/11/08

[#389928] Forming a Ruby meetup group... — "Darryl L. Pierce" <mcpierce@...>

Where I work we have a local Ruby group that used to meet up, until the

12 messages 2011/11/09

[#389950] The faster way to read files — "Noé Alejandro" <casanejo@...>

Does anybody know which is the fastest way to read a file? Lets say

18 messages 2011/11/09

[#390064] referring to version numbers in a gem — Chad Perrin <code@...>

How do I specify and access a gem's version number within the code of the

28 messages 2011/11/11

[#390238] RVM problem, plz help — Misha Ognev <b1368810@...>

Hi, I have this problem:

15 messages 2011/11/16

[#390308] any command line tools for querying yaml files — Rahul Kumar <sentinel1879@...>

(Sorry, this is not exactly a ruby question).

11 messages 2011/11/18

[#390338] Newbie - cmd question — Otto Dydakt <ottodydakt@...>

I've literally JUST downloaded ruby from rubyinstaller.org.

21 messages 2011/11/19
[#390342] Re: Newbie - cmd question — Otto Dydakt <ottodydakt@...> 2011/11/19

OK thank you, I uninstalled & reinstalled, checking the three boxes at

[#390343] Re: Newbie - cmd question — "Ian M. Asaff" <ian.asaff@...> 2011/11/19

did you type "irb" first to bring up the ruby command prompt?

[#391154] Re: Newbie - cmd question — "Hussain A." <hahmad@...> 2011/12/12

Hi all,

[#391165] Re: Newbie - cmd question — Luis Lavena <luislavena@...> 2011/12/12

Hussain A. wrote in post #1036281:

[#390374] Principle of Best Principles — Intransition <transfire@...>

I seem to run into a couple of design issue a lot and I never know what is

16 messages 2011/11/20

[#390396] how to call Function argument into another ruby script. — hari mahesh <harismahesh@...>

Consider I have a ruby file called library.rb.

10 messages 2011/11/21

[#390496] How to make 1.9.2 my default version using RVM — Fily Salas <fs_tigre@...>

Hi,

25 messages 2011/11/24

[#390535] Is high-speed sorting impossible with Ruby? — "Gaurav C." <chande.gaurav@...>

Well, first of all, I'm new to Ruby, and to this forum. So, hello. :)

39 messages 2011/11/25
[#390580] Re: Is high-speed sorting impossible with Ruby? — Joao Pedrosa <joaopedrosa@...> 2011/11/27

Hi,

[#390593] Re: Is high-speed sorting impossible with Ruby? — "Gaurav C." <chande.gaurav@...> 2011/11/27

Joao Pedrosa wrote in post #1033884:

[#390600] Re: Is high-speed sorting impossible with Ruby? — Douglas Seifert <doug@...> 2011/11/27

A big gain can be had by disabling the garbage collector. Here is my best

[#390601] Re: Is high-speed sorting impossible with Ruby? — Douglas Seifert <doug@...> 2011/11/27

I've thrown various solutions up on github here:

[#390689] Stupid question — James Gallagher <lollyproductions@...>

Hi everyone.

22 messages 2011/11/30

Re: What happens in dual sorts with nil values?

From: Robert Klemme <shortcutter@...>
Date: 2011-11-04 23:11:02 UTC
List: ruby-talk #389738
On Fri, Nov 4, 2011 at 6:49 PM, Wayne Brissette <waynefb@earthlink.net> wrote:
> I've put together an array that has a map. I did this so I could do some multi-level sorting of data. For example, if I had a map with:
>
> Struct.new(:first, :last, :age)
>
> And let's say I only had some of the ages, so some values were nil.
>
> Doing a multi-level sort using
>
> person.sort_by! { |a| [a.last, a.first, a.age]}
>
> gives me a list sorted correctly by last name, then first, and age?? (maybe, I need to test more)
>
> If I put the sort_by with a.age first, then I get an error.
>
> `block in <top (required)>': undefined local variable or method `ball_map' for main:Object (NameError)

Where does "ball_map" come from?  It's not in the code you've shown.

> I'm assuming this is because I'm trying to sort integers and have one with a nil value. So my question really is two-fold. Can I sort based on age if some values are nil? (doesn't look like it),

See Bartoz's suggestion.

> and second, am I fooling myself into thinking that I'm sorting on a.age when it's not the first sort value?

You're not fooling yourself.  But the order determines the precedence.
 The second field is only evaluated if the first fields are equal and
so forth.

Kind regards

robert

-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/

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