[#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: Ruby Challenge

From: Sylvester Keil <sylvester.keil@...>
Date: 2011-11-05 10:40:16 UTC
List: ruby-talk #389748
On Nov 5, 2011, at 5:59 AM, teresa nuagen wrote:

> Thomas Sawyer wrote in post #1030247:
>> Why does this sound like a school assignment?
>> 
>>    file = 'sample.txt'
>>    freq = Hash.new{|h,k| h[k] = 0}
>>    File.read(file).scan(/\w+/) do |w|
>>      freq[w] += 1
>>    end
>>    freq.each do |w,c|
>>      puts "#{c} #{w}"
>>    end
>> 
>> Untested.
> 
> 
> There should be an "if" / "else" statement in a looping method, to add 
> the word in list or word count.

Careful, you don't want to annoy the people who help you. The code solves your problem admirably: paste this (don't copy the ### marks) into a file and run it, and you will get exactly the output you wanted:

###

freq = Hash.new{|h,k| h[k] = 0}
DATA.read.scan(/\w+/) do |w|
	freq[w.downcase] += 1
end
freq.each.sort_by {|w,c| [c,w] }.each do |w,c|
	puts "#{c} #{w}"
end

__END__

If the text file contained this sentence, the output of your program
would look something like this

###

Before claiming a proposed solution to a 'challenge' you posted is missing something, have the decency at least to run it to see if it works. In this case, Intransition's solution sets the counter for each word to zero (this is what the first line does: if you add a word to the freq hash for the first time the counter is set to zero). The scan method is your 'looping method' and executes the block at each iteration. Finally, `freq[w.downase] += 1` increases the counter for each word. By defining, the zero default, Intransition's solution doesn't require your if/else statement. So, please, next time, instead of simply stating 'there should be an if/else statement there', how about 'cool solution! Can you explain to me why this works without an explicit if/else statement?'.



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