# Statistician III (#177)

**URL:** <https://www.ruby-forum.com/t/statistician-iii-177/148496>\
**Category:** Ruby\
**Created:** [September 13, 2008, 5:13pm UTC](https://www.ruby-forum.com/t/statistician-iii-177/148496 "2008-09-13T17:13:39Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![mansfiem](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/fbc32d/32.png) [@mansfiem](https://www.ruby-forum.com/u/mansfiem)\
**Post date:** [September 13, 2008, 5:13pm UTC](https://www.ruby-forum.com/t/statistician-iii-177/148496/1 "2008-09-13T17:13:39Z")

</div>

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## Statistician III

For this week’s quiz, we finish the Statistician series. If you don’t  
recall, go back and look at quizzes #167 and #168, where we built a  
module that collects line-based data with the help of some simple  
metaprogramming. However, there are three more things that I’d like  
implemented in the Statistician module, and that is your task this  
week.

First, add support for numeric fields. In the current implementations,  
everything is treated as a string, which forces the client to do the  
necessary conversion. A field should remain the default type, if the  
client does not specify a field as numeric.

Second, add support for client-specified default values. If the client  
does not provide defaults, use zero and the empty string (for numeric  
and string fields respectively).

Third, add a few basic statistics methods, so the client need not  
implement typical behavior. For numeric fields, this would be `min`,  
`max`, `mean` (i.e. average), and `sum`. For string fields, try `mode`  
(i.e. most frequent) or `freq` (i.e. percent frequency a particular  
string appears in a field). Go nuts and add other methods, if so  
inclined.

I leave the design of these features up to you, but if you want an  
example to code to, then extend one of the solutions from quiz #168 to  
implement this client file:

```
require 'statistician'

class Defense < Statistician::Reportable
  rule "[The]<name> wounds you[with <attack>] for <amount>

```

point[s] of [damage]."  
rule “You are wounded for point[s] of damage.”

```
  field :amount, 0 # recognize 0 as numeric, sets field

```

type to numeric and default to zero  
field :kind, “Common” # field type remains string, default set  
to “Common”  
end

```
# Other similarly extended Reportable classes go here... See quiz 

```

#168.

```
if __FILE__ == $0
  lotro = Statistician::Reporter.new(Defense, Offense, Defeat, 

```

Victory,  
Healing, Regen, Comment,  
Ignored)  
lotro.parse(File.read(ARGV[0]))

```
  puts <<-EOT
Number of Offense records: #{Offense.size} # Note: slightly

```

different from quiz #168  
Total damage inflicted: #{Offense.sum.amount}  
Average damage per Offense: #{Offense.mean.amount}

```
Most frequently hit creature: #{Offense.mode.name}
  EOT
end

```

Your solution may be based on a submission from quiz #168, though  
completely rewritten solutions are also welcome (as long as they still  
implement the requirements of those two earlier quizzes).

---

<div class="post-metadata">

**Author:** ![mansfiem](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/fbc32d/32.png) [@mansfiem](https://www.ruby-forum.com/u/mansfiem)\
**Post date:** [September 17, 2008, 4:05pm UTC](https://www.ruby-forum.com/t/statistician-iii-177/148496/2 "2008-09-17T16:05:48Z")

</div>

No takers, eh?

Okay, I’ll find a replacement #177 for Friday.