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from manimlib.imports import*
import math as m
class firstScene(ThreeDScene):
def construct(self):
axes = ThreeDAxes().scale(1.15)
surface = ParametricSurface(
lambda u, v: np.array([
u,
v,
m.exp(-10*u**2-10*v**2) #---- f(x,y)
]),u_min=-2,u_max=1, v_min=-1,v_max=1,checkerboard_colors=[PURPLE_C,PURPLE_D,PURPLE_E,PURPLE_B]).scale(3).shift([1.1,0.48,1.731])
trace = ParametricSurface(
lambda u, v: np.array([
m.exp(np.cos(v)+np.sin(v)),
v,
u/4
]), v_min = -1, v_max= 2).rotate(1.571,DOWN).shift(2.15*LEFT+[0.6,-0.4,1.54]).scale(1).set_color('#800000')
d = Dot(color =YELLOW).shift([1.9,0.7,4.1]) #---- critical point
tangent_line = Line(color = '#228B22').scale(1).shift([1.9,0.7,4.1]).rotate(4.5) #---- tangent along y axis
label_x = TextMobject("$x$").shift([5.8,-0.5,0])
label_y = TextMobject("$y$").shift([-0.5,5.6,0]).rotate(-4.5)
f_text = TextMobject("Tangent to the trace with $y$ constant at critical point").shift(3*RIGHT+2*UP).scale(0.5).to_corner(UL)
self.add(axes)
self.set_camera_orientation(phi=60*DEGREES,theta=15*DEGREES)
self.add(label_x)
self.add(label_y)
self.play(Write(surface))
self.wait(1)
self.add_fixed_in_frame_mobjects(s_text)
self.add(trace)
self.wait(1)
self.play(Write(tangent_line),Write(d))
self.wait(2)
class secondScene(ThreeDScene):
def construct(self):
axes = ThreeDAxes().scale(1.15)
surface = ParametricSurface(
lambda u, v: np.array([
u,
v,
m.exp(-10*u**2-10*v**2) #---- f(x,y)
]),u_min=-1,u_max=1, v_min=-1,v_max=1,checkerboard_colors=[PURPLE_C,PURPLE_D,PURPLE_E,PURPLE_B]).scale(3).shift([1.1,0.48,1.731])
trace = ParametricSurface(
lambda u, v: np.array([
m.exp(np.cos(v)+np.sin(v)),
v,
u/4
]), v_min = -1, v_max= 2).rotate(1.571,DOWN).shift(2.15*LEFT+[0.6,-0.4,1.54]).scale(1).set_color('#800000')
d = Dot(color =YELLOW).shift([1.9,0.7,4.1]) #---- critical point
label_x = TextMobject("$x$").shift([5.8,-0.5,0])
label_y = TextMobject("$y$").shift([-0.5,5.6,0]).rotate(-4.5)
f_text = TextMobject("Tangent to the trace with $y$ constant at critical point").shift(3*RIGHT+2*UP).scale(0.5).to_corner(UL)
tangent_line = Line(color = '#228B22').scale(1).shift([1.9,0.7,4.1]) #---- tangent along x axis
self.add(axes)
self.set_camera_orientation(phi=60*DEGREES,theta=15*DEGREES)
self.add(label_x)
self.add(label_y)
self.play(Write(surface))
self.wait(1)
self.add_fixed_in_frame_mobjects(f_text)
trace.rotate(-5).shift(0.2*RIGHT+0.8*UP+[0.6,-0.4,0.6])
self.add(trace)
self.play(Write(tangent_line),Write(d))
self.wait(1)
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