Matrix

# File lib/gnuplot.rb, line 307
def to_gplot (x = nil, y = nil)
  xgrid = x || (0...self.column_size).to_a
  ygrid = y || (0...self.row_size).to_a

  f = ""
  ygrid.length.times do |j|
    y = ygrid[j]
    xgrid.length.times do |i|
      if ( self[j,i] ) then
        f << "#{xgrid[i]} #{y} #{self[j,i]}\n"
      end
    end
  end
  
  f
end