Class: Matrix

Inherits:
Object show all
Defined in:
lib/epitools/core_ext/matrix.rb

Overview

Matrix extensions

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.ones(*dims) ⇒ Object

Build an array of 1’s



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# File 'lib/epitools/core_ext/matrix.rb', line 25

def self.ones(*dims)
  build(*dims) { 1 }
end

.random(*dims) ⇒ Object

Create a matrix of the specified size full of random numbers.



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# File 'lib/epitools/core_ext/matrix.rb', line 32

def self.random(*dims)
  build(*dims) { rand }
end

Instance Method Details

#blit!(submatrix, top, left) ⇒ Object Also known as: overlay!

Overlay one matrix onto another



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# File 'lib/epitools/core_ext/matrix.rb', line 83

def blit!(submatrix, top, left)
  submatrix.each_row.with_index do |row, y|
    row.each.with_index do |elem, x|
      self[top+y,left+x] = elem
    end
  end
end

#each_row ⇒ Object

Iterate over rows (takes a block or returns an Enumerator)



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# File 'lib/epitools/core_ext/matrix.rb', line 46

def each_row
  return to_enum(:each_row) unless block_given?

  (0...row_count).each do |num|
    yield row(num)
  end
end

#print(header = true, separator = " ") ⇒ Object Also known as: draw

Print the matrix to the STDOUT.



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# File 'lib/epitools/core_ext/matrix.rb', line 57

def print(header=true, separator=" ")
  max_width = map {|num| num.to_s.size }.max

  case first
  when Integer
    justify = :rjust
  when Float
    justify = :ljust
  else
    raise "Unknown matrix element type: #{first.class}"
  end

  # print it!
  puts "#{size.join("x")} matrix:" if header

  rows.each do |row|
    puts "  " + row.map { |n| n.to_s.send(justify, max_width) }.join(separator)
  end

  puts
end

#size ⇒ Object

The size of the matrix, returned as ‘[rows, columns]`.



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# File 'lib/epitools/core_ext/matrix.rb', line 39

def size
  [row_size, column_size]
end