Class: Array

Inherits:
Object show all
Defined in:
lib/bsearch.rb,
lib/builtinME.rb

Instance Method Summary collapse

Instance Method Details

#bsearch_first(range = 0 ... self.length, &block) ⇒ Object Also known as: bsearch

This method searches the FIRST occurrence which satisfies a condition given by a block in binary fashion and return the index of the first occurrence. Return nil if not found.



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# File 'lib/bsearch.rb', line 67

def bsearch_first (range = 0 ... self.length, &block)
  boundary = bsearch_lower_boundary(range, &block)
  if boundary >= self.length || yield(self[boundary]) != 0
    return nil
  else
    return boundary
  end
end

#bsearch_last(range = 0 ... self.length, &block) ⇒ Object

This method searches the LAST occurrence which satisfies a condition given by a block in binary fashion and return the index of the last occurrence. Return nil if not found.



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# File 'lib/bsearch.rb', line 100

def bsearch_last (range = 0 ... self.length, &block)
  # `- 1' for canceling `lower + 1' in bsearch_upper_boundary.
  boundary = bsearch_upper_boundary(range, &block) - 1

  if (boundary <= -1 || yield(self[boundary]) != 0)
    return nil
  else
    return boundary
  end
end

#bsearch_lower_boundary(range = 0 ... self.length, &block) ⇒ Object

Return the lower boundary. (inside)



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# File 'lib/bsearch.rb', line 48

def bsearch_lower_boundary (range = 0 ... self.length, &block)
  lower  = range.first() -1
  upper = if range.exclude_end? then range.last else range.last + 1 end
  while lower + 1 != upper
    mid = ((lower + upper) / 2).to_i # for working with mathn.rb (Rational)
    if yield(self[mid]) < 0
	lower = mid
    else
	upper = mid
    end
  end
  return upper
end

#bsearch_range(range = 0 ... self.length, &block) ⇒ Object

Return the search result as a Range object.



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# File 'lib/bsearch.rb', line 114

def bsearch_range (range = 0 ... self.length, &block)
  lower = bsearch_lower_boundary(range, &block)
  upper = bsearch_upper_boundary(range, &block)
  return lower ... upper
end

#bsearch_upper_boundary(range = 0 ... self.length, &block) ⇒ Object

Return the upper boundary. (outside)



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# File 'lib/bsearch.rb', line 81

def bsearch_upper_boundary (range = 0 ... self.length, &block)
  lower  = range.first() -1
  upper = if range.exclude_end? then range.last else range.last + 1 end
  while lower + 1 != upper
    mid = ((lower + upper) / 2).to_i # for working with mathn.rb (Rational)
    if yield(self[mid]) <= 0
	lower = mid
    else
	upper = mid
    end
  end
  return lower + 1 # outside of the matching range.
end

#inspect ⇒ Object Also known as: to_s 



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# File 'lib/builtinME.rb', line 196

def inspect
    str = "["
    is_first = true
    self.each() { |x|
        if (!is_first)
            str << ", "
        end
        is_first = false
        str << x.inspect
    }
    str << "]"
end

#join(sepString = "") ⇒ Object

def to_a

    self
end



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# File 'lib/builtinME.rb', line 181

def join(sepString="")
    return to_s if sepString.nil? || sepString == ""
		
    result = ""
    (length - 1).times do |index|
        result += (self[index].to_s) + sepString
    end
    result += self[length - 1].to_s if length != 0
    result
end

#reject ⇒ Object 



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# File 'lib/builtinME.rb', line 167

def reject
  a = []
  each {|x|
    if !yield x
      a << x
    end
  }
  a
end