simple txt grapher

star_curves.rb

def stars(y,scale,char);y>0 ? char * ((y*scale).round) : '';end
def curve(n);(0..n+1).each.collect{|x| y=Math.sin(Math::PI*2*x/n); [x, y]};end
def star_set(y,scale,char_neg,char_zero,char_pos); yn = y < 0 ? stars(-y,scale,char_neg) : ''; yp = y > 0 ? stars(y,scale,char_pos) : ''; ("%#{scale.round.to_i}s" % yn) + char_zero + ("%-#{scale.round.to_i}s" % yp); end
def star_set_def(y);star_set(y,10,'-','.','+');end
puts curve(16).collect{|n| star_set_def(n[1])+" #{n[0]}, #{n[1]}\n"}.join('')

=begin
          .           0, 0.0
          .++++       1, 0.3826834323650898
          .+++++++    2, 0.7071067811865475
          .+++++++++  3, 0.9238795325112867
          .++++++++++ 4, 1.0
          .+++++++++  5, 0.9238795325112867
          .+++++++    6, 0.7071067811865476
          .++++       7, 0.3826834323650899
          .           8, 1.2246467991473532e-16
      ----.           9, -0.38268343236508967
   -------.           10, -0.7071067811865475
 ---------.           11, -0.9238795325112865
----------.           12, -1.0
 ---------.           13, -0.9238795325112866
   -------.           14, -0.7071067811865477
      ----.           15, -0.3826834323650904
          .           16, -2.4492935982947064e-16
          .++++       17, 0.38268343236508995
=end