diff options
Diffstat (limited to 'FSF-2020/calculus-of-several-variables/integrals-of-multivariable-functions/fubini's-theorem/file3_iteration_methods.py')
| -rw-r--r-- | FSF-2020/calculus-of-several-variables/integrals-of-multivariable-functions/fubini's-theorem/file3_iteration_methods.py | 429 |
1 files changed, 429 insertions, 0 deletions
diff --git a/FSF-2020/calculus-of-several-variables/integrals-of-multivariable-functions/fubini's-theorem/file3_iteration_methods.py b/FSF-2020/calculus-of-several-variables/integrals-of-multivariable-functions/fubini's-theorem/file3_iteration_methods.py new file mode 100644 index 0000000..ad78a0b --- /dev/null +++ b/FSF-2020/calculus-of-several-variables/integrals-of-multivariable-functions/fubini's-theorem/file3_iteration_methods.py @@ -0,0 +1,429 @@ +from manimlib.imports import * + +class IterationMethods(GraphScene): + CONFIG = { + "x_min" : 0, + "x_max" : 1, + "y_min" : 0, + "y_max" : 1, + "x_tick_frequency" : 1, + "y_tick_frequency" : 1, + "x_labeled_nums": list(np.arange(0,2)), + "y_labeled_nums": list(np.arange(0 ,2)), + "x_axis_width": 6, + "y_axis_height": 6, + "graph_origin": ORIGIN+4.5*LEFT+3*DOWN, + "area_color": PINK , + "area_opacity": .6, + } + + def construct(self): + X = RIGHT*self.x_axis_width/(self.x_max- self.x_min) + Y = UP*self.y_axis_height/(self.y_max- self.y_min) + + self.intro_scene() + self.setup_axes(animate=True) + + + curve1= self.get_graph( + lambda x : x**2 , + x_min = 0, + x_max = 1, + color = ORANGE) + c1_eqn=self.get_graph_label( + curve1, + label="y=x^2", + x_val=.5, + direction=RIGHT, + buff=MED_LARGE_BUFF, + color=ORANGE, + ) + + curve2= self.get_graph( + lambda x : x , + x_min = 0, + x_max = 1, + color = YELLOW) + c2_eqn=self.get_graph_label( + curve2, + label="y=x", + x_val=.7, + direction=LEFT, + buff=MED_LARGE_BUFF, + color=YELLOW, + ) + self.curve1=curve1 + self.curve2=curve2 + + caption_limit=TextMobject(r"Observe the limits\\ of integration").to_corner(UR) + int_lim=TextMobject( + "$$\\int_0^1$$" + ).next_to( + caption_limit,DOWN,buff=.5 + ).align_to( + caption_limit,LEFT + ) + self.int_lim=int_lim + self.play(ShowCreation(VGroup(curve1,curve2)),Write(VGroup(c2_eqn,c1_eqn))) + + self.play(Write(caption_limit)) + self.get_rects() + self.show_integral_values_at_different_x() + self.wait(1) + self.integral_setup(int_lim,first_y=True) + + + self.another_method_scene() + self.remove(self.area) + self.wait() + + c1_eqn_y=self.get_graph_label( + curve1, + label="x=\sqrt y", + x_val=.6, + direction=RIGHT, + buff=MED_LARGE_BUFF, + color=ORANGE, + ) + c2_eqn_y=self.get_graph_label( + curve2, + label="x=y", + x_val=.7, + direction=LEFT, + buff=MED_LARGE_BUFF, + color=YELLOW, + ) + self.play( + ReplacementTransform(c1_eqn,c1_eqn_y), + ReplacementTransform(c2_eqn,c2_eqn_y) + ) + self.get_rects(base_y=True) + self.show_integral_values_at_different_y() + self.wait(1) + + int_lim_y=int_lim.copy() + int_lim_y.next_to(int_lim,DOWN) + self.int_lim_y=int_lim_y + equal=TextMobject("$$=$$").next_to(int_lim_y,LEFT) + self.add(equal) + + self.integral_setup(int_lim_y,first_y=False) + + self.wait(2) + + ################### + def intro_scene(self): + text=TextMobject(r"How different orders of \textbf{iterated integral}\\ works over the same region ?" ) + self.play(Write(text),run_time=4) + self.wait(2) + self.play(FadeOut(text)) + + def another_method_scene(self): + text=TextMobject(r"The other method\\ of iteration") + text.next_to(self.curve1,UP,buff=-1) + self.play(GrowFromCenter(text)) + self.wait(2) + self.play(LaggedStart(FadeOut(text),lag_ratio=2)) + + def integral_setup(self,ref_object,first_y=True): + if first_y: + area=self.get_area() + self.area=area + self.play(FadeOut(self.brace_group)) + self.play(ApplyMethod( + self.y_int.next_to, + ref_object,RIGHT,buff=0) + ) + + self.play(ApplyMethod( + self.dx_label.next_to, + self.y_int,RIGHT), + ShowCreation(area), + Write(self.int_lim),run_time=4 + ) + else: + area=self.get_area(base_y=True) + self.area=area + self.play( + FadeOut(self.y_brace_group), + Rotate(self.x_int,PI/2) + ) + self.play(ApplyMethod( + self.x_int.next_to, + ref_object,RIGHT,buff=0) + ) + self.play(ApplyMethod( + self.dy_label.next_to, + self.x_int,RIGHT), + ShowCreation(area), + Write(self.int_lim_y),run_time=4 + ) + + def get_area(self,base_y=False): + if base_y: + area = self.bounded_riemann_rectangles_y( + lambda x: x, + lambda x: np.sqrt(x), + y_min = 0, + y_max = 1, + dy =.001, + start_color = self.area_color, + end_color = self.area_color, + fill_opacity =self.area_opacity, + stroke_width = 0, + ) + self.y_area = area + else: + area = self.bounded_riemann_rectangles( + self.curve1, + self.curve2, + x_min = 0, + x_max = 1, + dx =.001, + start_color = self.area_color, + end_color = self.area_color, + fill_opacity =self.area_opacity, + stroke_width = 0, + ) + self.area = area + + # self.transform_between_riemann_rects(self.rects,area) + return area + + def get_rects(self,base_y=False): + if base_y: + rects = self.bounded_riemann_rectangles_y( + lambda x: x, + lambda x: np.sqrt(x), + y_min = 0, + y_max = 1, + dy =.01, + start_color = self.area_color, + end_color = self.area_color, + fill_opacity =self.area_opacity, + stroke_width = 0, + ) + self.y_rects=rects + else: + rects = self.bounded_riemann_rectangles( + self.curve1, + self.curve2, + x_min = 0, + x_max = 1, + dx =.01, + start_color = self.area_color, + end_color = self.area_color, + fill_opacity =self.area_opacity, + stroke_width = 0, + ) + self.rects=rects + # self.transform_between_riemann_rects(self.area,rects) + + return rects + + def show_integral_values_at_different_x(self): + rects=self.rects + rect = rects[len(rects)*1//10] + dx_brace = Brace(rect, DOWN, buff = 0) + dx_label = dx_brace.get_text("$dx$", buff = SMALL_BUFF) + dx_brace_group = VGroup(dx_brace,dx_label) + rp=int(len(rects)/20) + rects_subset = rects[6*rp:7*rp] + + last_rect = None + for rect in rects_subset: + brace = Brace(rect, LEFT, buff =.1) + y_int = TexMobject("\\int_{x^2}^{x}dy")#.rotate(PI/2) + y_int.next_to(brace, LEFT, MED_SMALL_BUFF) + anims = [ + rect.set_fill, self.area_color, 1, + dx_brace_group.next_to, rect, DOWN, SMALL_BUFF + ] + if last_rect is not None: + anims += [ + last_rect.set_fill, None, 0, + # last_rect.set_fill, self.area_color, self.area_opacity, + ReplacementTransform(last_brace, brace), + ReplacementTransform(last_y_int, y_int), + ] + else: + anims += [ + GrowFromCenter(brace), + Write(y_int) + ] + self.play(*anims) + # self.wait(.2) + + last_rect = rect + last_brace = brace + last_y_int = y_int + + y_int = last_y_int + y_brace = last_brace + self.brace_group=VGroup(y_brace,dx_brace,rect) + self.y_int=y_int + self.dx_label=dx_label + + def show_integral_values_at_different_y(self): + rects=self.y_rects + rect = rects[len(rects)*1//10] + dy_brace = Brace(rect, LEFT, buff = 0) + dy_label = dy_brace.get_text("$dy$", buff = SMALL_BUFF) + dy_brace_group = VGroup(dy_brace,dy_label) + rp=int(len(rects)/20) + rects_subset = rects[5*rp:6*rp] + + last_rect = None + for rect in rects_subset: + brace = Brace(rect, DOWN, buff =.1) + x_int = TexMobject("\\int_{y}^{\sqrt y}dx").rotate(-PI/2) + x_int.next_to(brace, DOWN, SMALL_BUFF) + anims = [ + rect.set_fill, self.area_color, 1, + dy_brace_group.next_to, rect, LEFT, SMALL_BUFF + ] + if last_rect is not None: + anims += [ + last_rect.set_fill, None, 0, + # last_rect.set_fill, self.area_color, self.area_opacity, + ReplacementTransform(last_brace, brace), + ReplacementTransform(last_x_int, x_int), + ] + else: + anims += [ + GrowFromCenter(brace), + Write(x_int) + ] + self.play(*anims) + # self.wait(.2) + + last_rect = rect + last_brace = brace + last_x_int = x_int + + x_int = last_x_int + y_brace = last_brace + self.y_brace_group=VGroup(y_brace,dy_brace,rect) + self.x_int=x_int + self.dy_label=dy_label + + + def bounded_riemann_rectangles( + self, + graph1, + graph2, + x_min=None, + x_max=None, + dx=0.01, + input_sample_type="center", + stroke_width=1, + stroke_color=BLACK, + fill_opacity=1, + start_color=None, + end_color=None, + show_signed_area=True, + width_scale_factor=1.001 + ): + x_min = x_min if x_min is not None else self.x_min + x_max = x_max if x_max is not None else self.x_max + if start_color is None: + start_color = self.default_riemann_start_color + if end_color is None: + end_color = self.default_riemann_end_color + rectangles = VGroup() + x_range = np.arange(x_min, x_max, dx) + colors = color_gradient([start_color, end_color], len(x_range)) + for x, color in zip(x_range, colors): + if input_sample_type == "left": + sample_input = x + elif input_sample_type == "right": + sample_input = x + dx + elif input_sample_type == "center": + sample_input = x + 0.5 * dx + else: + raise Exception("Invalid input sample type") + graph1_point = self.input_to_graph_point(sample_input, graph1) + graph1_point_dx= self.input_to_graph_point(sample_input + width_scale_factor * dx, graph1) + graph2_point = self.input_to_graph_point(sample_input, graph2) + + points = VGroup(*list(map(VectorizedPoint, [ + graph1_point, + graph1_point_dx, + graph2_point + ]))) + + rect = Rectangle() + rect.replace(points, stretch=True) + if graph1_point[1] < self.graph_origin[1] and show_signed_area: + fill_color = invert_color(color) + else: + fill_color = color + rect.set_fill(fill_color, opacity=fill_opacity) + rect.set_stroke(stroke_color, width=stroke_width) + rectangles.add(rect) + return rectangles + + def bounded_riemann_rectangles_y( + self, + graph1, + graph2, + y_min=None, + y_max=None, + dy=0.01, + input_sample_type="center", + stroke_width=1, + stroke_color=BLACK, + fill_opacity=1, + start_color=None, + end_color=None, + show_signed_area=True, + width_scale_factor=1.001 + ): + y_min = y_min if y_min is not None else self.y_min + y_max = y_max if y_max is not None else self.y_max + if start_color is None: + start_color = self.default_riemann_start_color + if end_color is None: + end_color = self.default_riemann_end_color + rectangles = VGroup() + y_range = np.arange(y_min, y_max, dy) + colors = color_gradient([start_color, end_color], len(y_range)) + for y, color in zip(y_range, colors): + if input_sample_type == "left": + sample_input = y + elif input_sample_type == "right": + sample_input = y + dy + elif input_sample_type == "center": + sample_input = y + 0.5 * dy + else: + raise Exception("Invalid input sample type") + graph1_point = self.coords_to_point( + graph1(sample_input),sample_input + ) + dy_input=sample_input + width_scale_factor * dy + graph1_point_dy= self.coords_to_point( + graph1(dy_input),dy_input + ) + graph2_point = self.coords_to_point( + graph2(sample_input),sample_input + ) + + points = VGroup(*list(map(VectorizedPoint, [ + graph1_point, + graph1_point_dy, + graph2_point + ]))) + + rect = Rectangle() + rect.replace(points, stretch=True) + if graph1_point[1] < self.graph_origin[1] and show_signed_area: + fill_color = invert_color(color) + else: + fill_color = color + rect.set_fill(fill_color, opacity=fill_opacity) + rect.set_stroke(stroke_color, width=stroke_width) + rectangles.add(rect) + return rectangles + + +#uploaded by Somnath Pandit.FSF2020_Fubini's_Theorem |