Simple AI (Neural network) program by Ruby.

Neural network is an algorithm of AI (Artificial intelligence).

I wrote a symple Neural network program by Ruby.

This program judge if the total price of three candies are under the limit.

class Unit
  def initialize(count=3)
    @cells = []
    (count + 1).times { @cells << rand(9) }
  end

  def learn(patterns)
    while !ok ||= false
      ok = true
      result = []
      patterns.values.each do |pattern|
        ans = answer(pattern)
        chk = patterns.check(pattern)
        if ans == chk
          result << 'OK'
        elsif ans && !chk
          result << 'NG'
          ok = false
          penalize(pattern, -1)
        elsif !ans && chk
          result << 'NG'
          ok = false
          penalize(pattern, 1)
        end
      end
      yield(ok, result, @cells)
    end
  end

  def answer(pattern)
    sum = 0
    @cells.length.times { |i| sum += @cells[i + 1] if pattern[i] == 1 }
    @cells[0] <= sum
  end

  def penalize(pattern, direction)
    @cells[0] -= direction
    @cells.length.times { |i| @cells[i + 1] += direction if pattern[i] == 1 }
  end
end

class Patterns
  def initialize
    @limit = 500
    @prices = [310,220,70]
    @values =  [[0, 0, 0],
                [0, 0, 1],
                [0, 1, 0],
                [0, 1, 1],
                [1, 0, 0],
                [1, 0, 1],
                [1, 1, 0],
                [1, 1, 1]]
  end

  attr_reader :values

  def check(pattern)
    sum = 0
    pattern.length.times { |i| sum += @prices[i] * pattern[i] }
    sum <= @limit
  end
end

#--------------------------------
unit = Unit.new
pat = Patterns.new
unit.learn(pat) do |ok, result, cells|
  p result
  break if gets =~ /x/
end

Simple AI (Generic Algorithm) program by Ruby.

Generic Algorithm is an algorithm of AI (Artificial intelligence).

I wrote a symple Generic Algorithm program by Ruby.

It answers multiple-choice questions.

class Genes
  def initialize(gene_count=10, quiz_count=10)
    @generation = 1
    @quiz = Quiz.new(quiz_count)
    while max == quiz_count
      @genes = []
      gene_count.times { |i| @genes << Gene.new(quiz_count) }
      mark()
      sort()
    end
  end

  def start
    while max < @quiz.count
      yield(@generation, @genes, max, min, average)
      next_genration()
      mark()
      sort()
    end
      yield(@generation, @genes, max, min, average)
  end

  def mark
    @genes.length.times { |i| @genes[i].score = @quiz.mark(@genes[i].ans) }
  end

  def sort
    @genes.sort! { |a, b| a.score <=> b.score }.reverse!
  end

  def next_genration
    @generation += 1
    pair = []
    pair << @genes[0]
    pair << @genes[1]
    pair = breed(pair)
    @genes[@genes.length - 2] = pair[0]
    @genes[@genes.length - 1] = pair[1]
  end

  def breed(parents)
    c = parents[0].count
    children = [Gene.new(c), Gene.new(c)]
    cross = rand(c - 1)
    c.times do |i|
      n = (i < cross) ? 0 : 1
      children[0].ans[i] = parents[(0+n)%2].ans[i]
      children[1].ans[i] = parents[(1+n)%2].ans[i]
    end

    mutation = rand(c)
    children[0].ans[mutation] = rand(3) if mutation < c
    mutation = rand(c)
    children[1].ans[mutation] = rand(3) if mutation < c
    children
  end

  def max
    @genes ? @genes[0].score : @quiz.count
  end

  def min
    @genes ? @genes[(@genes.length - 1)].score : 0
  end

  def average
    sum = 0
    @genes.each { |x| sum += x.score }
    sum / @genes.length
  end
end

class Gene
  def initialize(count)
    @count = count
    @ans = []
    @count.times { |i| @ans << rand(3) }
  end

  attr_accessor :score
  attr_reader :ans
  attr_reader :count
end

class Quiz < Gene
  def mark(ans)
    score = 0
    @count.times { |i| score += 1 if @ans[i] == ans[i] }
    score
  end
end

#--------------------------------
g = Genes.new
g.start do |generation, genes, max, min, average|
  p generation
  p max
  10.times do |i|
    p genes[i].ans
  end
  break if gets =~ /x/
end

Currying of a function with unfixed argument.

Some examples of Function Currying.

(define (curried+ a)
  (lambda (b) (+ a b)))

((curried+ 1) 2)

(define (curried-mean a)
  (lambda (b)
    (lambda (c) (/ (+ (+ a b) c) 3))))

(((curried-mean 1) 2) 3)

When the function has arguments with which the number is unfixed.

(define (append lst x)
  (if (null? lst)
    (list x)
    (let ((l (if (list? lst) lst (list lst))))
      (cons (car l) (append (cdr l) x)))))

(define (curried-list x)
  (lambda (y)
    (if (null? y)
      x
      (curried-list (append x y)))))

(((((curried-list 1) 2) 3) 4) '())

"'()" is unwanted...

Tail recursion of Scheme.

Ruby program for Fibonacci number.

def fib(n)
 if n < 2
   n
 else
   fib(n - 2) + fib(n - 1)
 end
end

Scheme program for Fibonacci number.

(define (fib n)
 (if (< n 2)
   n
   (+ (fib (- n 1)) (fib (- n 2)))))

Tail recursion version.

(define (fib n)
 (define (fib-iter n a b)
   (if (zero? n)
     a
     (fib-iter (- n 1) b (+ a b))))
 (fib-iter n 0 1))

Scheme has "tail recursion optimization".
Then Scheme is faster than Ruby with optimization.

The one line C#3.0 program for Fibonacci numbers.

I wrote one line Ruby program for Fibonacci numbers.
The one line Ruby program for Fibonacci numbers.

And I wrote one line C#2.0 program for it.
The one line C#2.0 program for Fibonacci numbers.


C#3.0 program is more elegant than C#2.0 program.

Let's write one line C#3.0 program for Fibonacci numbers.

This is the result.

1
1
2
3
5
8
13
21
34
55

This is the one line C#2.0 program.

new EventHandler(delegate(object s,EventArgs e){while(((int[])s)[2]++<10)if(Console.WriteLine(((int[])s)[1]=(((int[])s)[0]=((int[])s)[0]+((int[])s)[1])-((int[])s)[1])is Object){}}).Invoke(new int[]{1,0,0},null);

And this is the one line C#3.0 program.

Enumerable.Repeat(new[]{1,0},10).All(x=>!(Console.WriteLine(x[1]=((x[0]=x[0]+x[1])-x[1]))is Object));

More elegant!

The one line C#2.0 program for Fibonacci numbers.

I wrote one line Ruby program for Fibonacci numbers.
The one line Ruby program for Fibonacci numbers.

Ruby is a dynamically-typed programming language.
C# is a statically-typed programming language.

Let's write one line C#2.0 program for Fibonacci numbers.

This is the result.

1
1
2
3
5
8
13
21
34
55

This is the one line program.

new EventHandler(delegate(object s,EventArgs e){while(((int[])s)[2]++<10)if(Console.WriteLine(((int[])s)[1]=(((int[])s)[0]=((int[])s)[0]+((int[])s)[1])-((int[])s)[1])is Object){}}).Invoke(new int[]{1,0,0},null);

This is the statically-typed programming language.

"Jobs Hacks" are not for sale.

I made this "O'Reilly Maker".
O'Reilly Maker - Create a funny book cover!
O'Reilly Maker - Jobs hacks


From Steve Jobs Stanford Commencement Speech 2005.

"Keep looking. Don't settle."

"Your time is limited, so don't waste it living someone else's life."

"Stay Hungry. Stay Foolish."

The one line Ruby program for Fibonacci numbers.

Let's write one line Ruby program for Fibonacci numbers.

This is the result.

1
1
2
3
5
8
13
21
34
55

This is the one line program.

lambda{|a,b|10.times{p b=(a=a+b)-b}}.call(1,0)

Smart?

Can't use "document.body" on Safari.

It's impossible to use "document.body" on Safari when the web page is XHTML.
Then this code return "undefined".

alert(typeof(document.body));

But it comes no always.
What is the condition?


"document.documentElement" is OK.

Read Offline for iPhone/iPod touch

I made a bookmarklet for iPhone/iPod touch.
You can read web pages on iPhone/iPod touch when you are offline.

Read Offline for iPhone/iPod touch

I'm glad to read web pages offline.

JavaScript Shell for iPhone/iPod touch

JavaScript Shell for iPhone/iPod touch was released.

You can write and execute JavaScript programs on iPhone/iPod touch even if you are offline.


This is bookmarklet version.
JavaScript Shell for iPhone/iPod touch

It's posible to save your script with ver.2.
JavaScript Shell for iPhone/iPod touch (ver.2)


Sample code:

Show messagebox.

alert("Hello, world");

Calculate fibonacci.

function fib(n) {
  if (n < 2) {
    return n;
  } else {
    return fib(n - 1) + fib(n - 2);
  }
}
fib(10);

Operate DOM.

document.getElementById("area").style.color = "blue";
document.getElementById("result").style.color = "red";
document.getElementById("exec").innerHTML = "Execute!!!!";
document.getElementById("save").innerHTML = "Save!!!!";

Let's enjoy programming on iPhone/iPod touch.

iPod touch firmware update to 1.1.3

I updated my iPod touch firmware to 1.1.3.

The information about the firmware 1.1.3 and the software update is mixed.
The firmware 1.1.3 is free.
Software update is nonfree ($20).

The firmware is good for Japanese users.
Because of the improvement of Japanese keybord.

I'm looking forward to the SDK for iPhone/iPod touch released next month.

The one line Ruby program for the factorial of n (n!)

Write a program that calculates the facctorial of n (n!).

result = n * (n - 1) * (n - 2) * ... * 2 * 1


I write a Ruby program.

n = gets.to_i
k = 1
n.times do |i|
k *= i.next
end
puts k

This is a normal program.
Let's write in one line.

k = 1
gets.to_i.times { |i| k *= i.next }
puts k

It's easy so far.


A little device.

k = 1
puts k if gets.to_i.times { |i| k *= i.next }

The key point is the initialization of a variable.

lambda { |k| puts k if gets.to_i.times { |i| k *= i.next } }.call(1)

Completion!

My iPod touch can't access WiFi.

I want to jailbreak for my iPod touch.
But my iPod touch can't access WiFi.
The wireless connection is unstable.

Should I buy other wireless router?

Trying iPod touch

I got an iPod touch.
And got a case for it.

But the case is not good.
I will buy a new case.

From Japanese programmer.

I use C# at office and Ruby at home.
Now I'm interested in JavaScript.

I've just been reading "The Pragmatic Programmer" written by Andrew Hunt and David Thomas.