Create file3_non_differentiable_function.py

Manim code for Video 3 of lecture note on the subtopic Tangent Plane Approximations

1 files changed, 30 insertions, 0 deletions

diff --git a/FSF-2020/approximations-and-optimizations/Tangent-Plane-Approximations/file3_non_differentiable_function.py b/FSF-2020/approximations-and-optimizations/Tangent-Plane-Approximations/file3_non_differentiable_function.py
new file mode 100644
index 0000000..13bd73e
--- /dev/null
+++ b/FSF-2020/approximations-and-optimizations/Tangent-Plane-Approximations/file3_non_differentiable_function.py
@@ -0,0 +1,30 @@
+from manimlib.imports import*
+import math
+
+#---- tangent plane does not exists for f(x,y): sqrt(x**2+y**2) at origin
+
+class TangenttoSurface(ThreeDScene):
+    def construct(self):
+        axes = ThreeDAxes() 
+        
+        #----f(x,y): sqrt(x**2+y**2)
+        p = ParametricSurface(
+            lambda u, v: np.array([
+                u,
+                v,
+                math.sqrt(u**2+v**2)
+            ]),v_min = -1,v_max = 1, u_min = -1, u_max = 1, checkerboard_colors = [RED_C,TEAL_D],
+            resolution = (20, 20)).scale(1)
+
+        self.set_camera_orientation(phi = 75 * DEGREES)  
+         
+        d = Dot([0,0,0],color = '#800000') #----critical point
+        d_text = TextMobject("$(0,0)$").scale(0.5).shift(0.2*DOWN)
+        f_text = TextMobject("$f$ is not differentiable at origin").scale(0.5).to_corner(UL)
+
+        self.begin_ambient_camera_rotation(rate=0.1) 
+        self.add(axes)
+        self.play(Write(p),Write(d))      
+        self.add_fixed_in_frame_mobjects(d_text)
+        self.add_fixed_in_frame_mobjects(f_text)
+        self.wait(2)