method

each

v2_4_6 - Show latest stable - 0 notes - Class: Matrix

1_8_6_287
1_8_7_72
1_8_7_330
1_9_1_378
1_9_2_180 (0)
1_9_3_125 (27)
1_9_3_392 (0)
2_1_10 (0)
2_2_9 (0)
2_4_6 (0)
2_5_5 (0)
2_6_3
What's this?

each(which = :all) public

Yields all elements of the matrix, starting with those of the first row, or returns an Enumerator if no block given. Elements can be restricted by passing an argument:

:all (default): yields all elements
:diagonal: yields only elements on the diagonal
:off_diagonal: yields all elements except on the diagonal
:lower: yields only elements on or below the diagonal
:strict_lower: yields only elements below the diagonal
:strict_upper: yields only elements above the diagonal
:upper: yields only elements on or above the diagonal

Matrix[ [1,2], [3,4] ].each { |e| puts e }
```
# => prints the numbers 1 to 4
```
Matrix[ [1,2], [3,4] ].each(:strict_lower).to_a # => [3]

Show source

# File lib/matrix.rb, line 463
  def each(which = :all) # :yield: e
    return to_enum :each, which unless block_given?
    last = column_count - 1
    case which
    when :all
      block = Proc.new
      @rows.each do |row|
        row.each(&block)
      end
    when :diagonal
      @rows.each_with_index do |row, row_index|
        yield row.fetch(row_index){return self}
      end
    when :off_diagonal
      @rows.each_with_index do |row, row_index|
        column_count.times do |col_index|
          yield row[col_index] unless row_index == col_index
        end
      end
    when :lower
      @rows.each_with_index do |row, row_index|
        0.upto([row_index, last].min) do |col_index|
          yield row[col_index]
        end
      end
    when :strict_lower
      @rows.each_with_index do |row, row_index|
        [row_index, column_count].min.times do |col_index|
          yield row[col_index]
        end
      end
    when :strict_upper
      @rows.each_with_index do |row, row_index|
        (row_index+1).upto(last) do |col_index|
          yield row[col_index]
        end
      end
    when :upper
      @rows.each_with_index do |row, row_index|
        row_index.upto(last) do |col_index|
          yield row[col_index]
        end
      end
    else
      raise ArgumentError, "expected #{which.inspect} to be one of :all, :diagonal, :off_diagonal, :lower, :strict_lower, :strict_upper or :upper"
    end
    self
  end

each

Related methods