to_s

# File lib/matrix.rb, line 1020
  def to_s
    if empty?
      "Matrix.empty(#{row_size}, #{column_size})"
    else
      "Matrix[" + @rows.collect{|row|
        "[" + row.collect{|e| e.to_s}.join(", ") + "]"
      }.join(", ")+"]"
    end
  end