1 files changed, 64 insertions, 0 deletions
diff --git a/FSF-2020/calculus-of-several-variables/multivariable-functions-and-paritial-derivatives/partial-derivatives/file6_clariant_rule.py b/FSF-2020/calculus-of-several-variables/multivariable-functions-and-paritial-derivatives/partial-derivatives/file6_clariant_rule.py
new file mode 100644
index 0000000..b79f77c
--- /dev/null
+++ b/FSF-2020/calculus-of-several-variables/multivariable-functions-and-paritial-derivatives/partial-derivatives/file6_clariant_rule.py
@@ -0,0 +1,64 @@
+from manimlib.imports import *
+
+class ClariantRule(Scene):
+    def construct(self):
+        derivatives = TextMobject(r"$cos(x)y^3$",r"$-sin(x)y^3$", r"$3cos(x)y^2$", r"$-cos(x)y^3$", r"$-3sin(x)y^2$", r"$-3sin(x)y^2$", r"$6cos(x)y$")
+
+        partial_derivatives = TextMobject(r"$\frac{\partial}{\partial x}$", r"$\frac{\partial}{\partial y}$")
+
+        
+        derivatives[0].move_to(2*UP).set_color(PURPLE)
+        derivatives[1].move_to(3*LEFT).set_color(YELLOW_C)
+        derivatives[2].move_to(3*RIGHT).set_color(BLUE_C)
+        
+        arrrow_1 = Arrow(derivatives[0].get_bottom(), derivatives[1].get_top())
+        arrrow_1_lab = partial_derivatives[0].copy().scale(0.7)  
+        arrrow_1_lab.move_to(2.5*LEFT+ 1.3*UP)
+
+        arrrow_2 = Arrow(derivatives[0].get_bottom(), derivatives[2].get_top())
+        arrrow_2_lab = partial_derivatives[1].copy().scale(0.7)  
+        arrrow_2_lab.move_to(2.5*RIGHT+ 1.3*UP)
+
+        self.play(Write(derivatives[0]))
+        self.play(GrowArrow(arrrow_1), GrowArrow(arrrow_2), Write(arrrow_1_lab), Write(arrrow_2_lab))
+
+        self.play(Write(derivatives[1]))
+        self.play(Write(derivatives[2]))
+
+        derivatives[3].move_to(2*DOWN + 4.5*LEFT).set_color(GREEN_C)
+        derivatives[4].move_to(2*DOWN + 1.5*LEFT).set_color(PINK)
+        derivatives[5].move_to(2*DOWN + 1.5*RIGHT).set_color(PINK)
+        derivatives[6].move_to(2*DOWN + 4.5*RIGHT).set_color(ORANGE)
+
+        arrrow_3 = Arrow(derivatives[1].get_bottom(), derivatives[3].get_top())
+        arrrow_3_lab = partial_derivatives[0].copy().scale(0.7) 
+        arrrow_3_lab.move_to(4.3*LEFT+ 0.8*DOWN)
+
+        arrrow_4 = Arrow(derivatives[1].get_bottom(), derivatives[4].get_top())
+        arrrow_4_lab = partial_derivatives[1].copy().scale(0.7)  
+        arrrow_4_lab.move_to(1.6*LEFT+ 0.8*DOWN)
+
+        arrrow_5 = Arrow(derivatives[2].get_bottom(), derivatives[5].get_top())
+        arrrow_5_lab = partial_derivatives[0].copy().scale(0.7)  
+        arrrow_5_lab.move_to(1.6*RIGHT+ 0.8*DOWN)
+
+        arrrow_6 = Arrow(derivatives[2].get_bottom(), derivatives[6].get_top())
+        arrrow_6_lab = partial_derivatives[1].copy().scale(0.7)  
+        arrrow_6_lab.move_to(4.3*RIGHT+ 0.8*DOWN)
+
+        self.play(GrowArrow(arrrow_3), GrowArrow(arrrow_4), Write(arrrow_3_lab), Write(arrrow_4_lab))
+        self.play(Write(derivatives[3]), Write(derivatives[4]))
+
+        self.play(GrowArrow(arrrow_5), GrowArrow(arrrow_6), Write(arrrow_5_lab), Write(arrrow_6_lab))
+        self.play(Write(derivatives[5]), Write(derivatives[6]))
+        
+        brace1 = Brace(derivatives[4:6], DOWN, buff = SMALL_BUFF, color = RED_C)
+        brace_t1 = brace1.get_text("Mixed partial derivatives are the same!")
+        brace_t1.set_color(RED_C)
+
+        self.play(GrowFromCenter(brace1), FadeIn(brace_t1))
+        
+        self.wait()
+
+
+