Class: RubyDataStructures::MultiDimensionalArray

Inherits:
Object
  • Object
show all
Defined in:
lib/RubyDataStructures/multi_dimensional_array.rb

Instance Method Summary collapse

Constructor Details

#initialize(*dimensions) ⇒ MultiDimensionalArray

Returns a new instance of MultiDimensionalArray.



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# File 'lib/RubyDataStructures/multi_dimensional_array.rb', line 2

def initialize(*dimensions)
  @dimensions = Array.new(dimensions.length)
  @factors = Array.new(dimensions.length)
  product = 1
  i = dimensions.length - 1

  while i >= 0
    @dimensions[i] = dimensions[i]
    @factors[i] = product
    product *= dimensions[i]
    i -= 1
  end

  @data = Array.new(product)
end

Instance Method Details

#[](*indices) ⇒ Object 



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# File 'lib/RubyDataStructures/multi_dimensional_array.rb', line 33

def [](*indices)
  @data[self.get_offset(indices)]
end

#[]=(*indices_and_value) ⇒ Object 



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# File 'lib/RubyDataStructures/multi_dimensional_array.rb', line 37

def []=(*indices_and_value)
  value = indices_and_value.pop
  @data[self.get_offset(indices_and_value)] = value
end

#get_offset(indices) ⇒ Object

Raises:

  • (IndexError) 


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# File 'lib/RubyDataStructures/multi_dimensional_array.rb', line 18

def get_offset(indices)
  raise IndexError if indices.length != @dimensions.length

  offset = 0

  (0..(@dimensions.length - 1)).each do |i|
    
    raise IndexError if indices[i] < 0 || indices[i] >= @dimensions[i]

    offset += @factors[i]*indices[i]
  end

  return offset
end