&in wall_file = 'rectangle.wall' / 
&in p%vec = 0, 0, 0, 0, 101, -1 /
&in p%vec = 0, 0, -0.06, 0, 101.1, 1 /
&in p%vec = 0, 0, 0, 0, 0, 1 /
&in p%vec = 0, 0.98, 0, 0.16, 0, 0.11832159566199 /
&in p%vec = 0,-0.92, 0, 0.37, 0, 0.12922847983320 /

&in wall_file = 'ellipse.wall' / 
&in p%vec = 0, 0.98, 0, 0.14, 0, 0.14142135623731 /
&in p%vec = 0, 0.58, 0, 0.80, 0, 0.15362291495737 /
&in p%vec = 0,-0.98, 0, 0.19, 0, 0.0591607978310 /

&in wall_file = 'rot_ellipse.wall' / 
&in p%vec = 0, 0.73, 0, 0.68, 0, 0.0685565460040 /
&in p%vec = 0, 0.39, 0, 0.91, 0, 0.28618176042508 /