Correct boat_animation example (capytaine#434)

docs/user_manual/examples/boat_animation.py

@@ -1,5 +1,4 @@
-import numpy as np
-from numpy import pi as π
+from numpy import pi
 
 import capytaine as cpt
 from capytaine.bem.airy_waves import airy_waves_free_surface_elevation
@@ -39,15 +38,15 @@ def setup_animation(body, fs, omega, wave_amplitude, wave_direction):
     diffraction_elevation = bem_solver.compute_free_surface_elevation(fs, diffraction_result)
 
     # Compute the wave pattern radiated by the RAO
-    radiation_elevations_per_dof = {res.radiating_dof: bem_solver.compute_free_surface_elevation(fs, diffraction_result) for res in radiation_results}
+    radiation_elevations_per_dof = {res.radiating_dof: bem_solver.compute_free_surface_elevation(fs, res) for res in radiation_results}
     radiation_elevation = sum(rao.sel(omega=omega, radiating_dof=dof).data * radiation_elevations_per_dof[dof] for dof in body.dofs)
 
     # SET UP ANIMATION
     # Compute the motion of each face of the mesh for the animation
     rao_faces_motion = sum(rao.sel(omega=omega, radiating_dof=dof).data * body.dofs[dof] for dof in body.dofs)
 
     # Set up scene
-    animation = Animation(loop_duration=2*π/omega)
+    animation = Animation(loop_duration=2*pi/omega)
     animation.add_body(body, faces_motion=wave_amplitude*rao_faces_motion)
     animation.add_free_surface(fs, wave_amplitude * (incoming_waves_elevation + diffraction_elevation + radiation_elevation))
     return animation
@@ -57,6 +56,6 @@ def setup_animation(body, fs, omega, wave_amplitude, wave_direction):
     body = generate_boat()
     fs = cpt.FreeSurface(x_range=(-100, 75), y_range=(-100, 75), nx=100, ny=100)
 
-    anim = setup_animation(body, fs, omega=1.5, wave_amplitude=0.5, wave_direction=π)
+    anim = setup_animation(body, fs, omega=1.5, wave_amplitude=0.5, wave_direction=pi)
     anim.run(camera_position=(70, 70, 100), resolution=(800, 600))
     anim.save("animated_boat.ogv", camera_position=(70, 70, 100), resolution=(800, 600))