1 files changed, 55 insertions, 0 deletions
diff --git a/FSF-2020/calculus/intro-to-calculus/intro-to-derivative/derivative1.py b/FSF-2020/calculus/intro-to-calculus/intro-to-derivative/derivative1.py
new file mode 100644
index 0000000..79a6fc6
--- /dev/null
+++ b/FSF-2020/calculus/intro-to-calculus/intro-to-derivative/derivative1.py
@@ -0,0 +1,55 @@
+from manimlib.imports import *
+class derivative1(GraphScene, Scene):
+	def setup(self):
+		GraphScene.setup(self)
+	CONFIG = {
+        "y_max" : 4,
+        "y_min" : -2,
+        "x_max" : 4,
+        "x_min" : -2,
+        "y_tick_frequency" : 1, 
+        "x_tick_frequency" : 1, 
+        "axes_color" : WHITE, 
+        "num_graph_anchor_points": 3000, #this is the number of points that graph manim
+        "graph_origin" : ORIGIN+2*DOWN+4*LEFT,
+        "x_labeled_nums": list(range(-2,5)),
+        "y_labeled_nums": list(range(-2,5)),
+        "x_axis_label":"$x$",
+        "y_axis_label":r"$f(x)=y= 3-\frac { 3 }{ 2 } x$",
+        "x_axis_width": 5,
+        "y_axis_height": 5,
+    }
+	def construct(self):
+		#XTD = self.x_axis_width/(self.x_max - self.x_min)
+		#YTD = self.y_axis_height/(self.y_max - self.y_min)
+
+		text1 = TextMobject("")
+		text2 = TexMobject("{y}_{2}-{y}_{1}")
+		text2 = TexMobject("{x}_{2}-{x}_{1}")
+		text3 = TexMobject(r"m\quad =\frac { { y }_{ 2 }-{ y }_{ 1 } }{ { x }_{ 2 }-{ x }_{ 1 } }").move_to(np.array([3,0,0]))
+		text4 = TexMobject(r"m\quad =\frac { 3 }{ -2 }").move_to(np.array([3,0,0]))
+		text5 = TexMobject(r"m\quad =\quad -1.5").move_to(np.array([3,0,0]))
+		self.setup_axes()
+		graph_1 = self.get_graph(lambda x : 3-1.5*x, color = GREEN_SCREEN, x_min = -1, x_max = 3)
+		graph_2 = self.get_graph(lambda x : 3.1-1.5*x, color = ORANGE, x_min = 0, x_max = 2)
+		dot1 = Dot()
+		dot2 = SmallDot(self.graph_origin+1.7*RIGHT, color = PINK)
+		dot3 = SmallDot(self.graph_origin+2.5*UP, color = RED_B)
+		vec1 = Vector(2.5*DOWN, color = PINK).shift(self.graph_origin+2.5*UP)
+		vec2 = Vector(1.7*RIGHT, color = RED_B).shift(self.graph_origin)
+		brace1 = Brace(vec1, LEFT)
+		brace2 = Brace(vec2, DOWN)
+		br1text = brace1.get_text(r"${y}_{2}-{y}_{1}$").next_to(brace1, LEFT)
+		br2text = brace2.get_text(r"${x}_{2}-{x}_{1}$").next_to(brace2, DOWN) 
+		self.play(ShowCreation(graph_1), ShowCreation(dot2), ShowCreation(dot3))
+		self.play(MoveAlongPath(dot1, graph_2), ShowCreation(vec1), ShowCreation(vec2), run_time = 3)
+		self.wait(1)
+		self.play(ShowCreation(brace1), ShowCreation(brace2))
+		self.play(ShowCreation(br1text), ShowCreation(br2text))
+		self.wait(2)
+		self.play(GrowFromCenter(text3))
+		self.wait(2.5)
+		self.play(ReplacementTransform(text3, text4))
+		self.wait(2)
+		self.play(ReplacementTransform(text4, text5))
+		self.wait(2)