Manim方程变换

Question

Manim社区v0.15.1

class Equation_Transformation_Bug(Scene):
    def construct(self):
        equation_1 = MathTex("w", "\\times","v", "=", "1")
        equation_1.shift(UP*2).scale(2)
        equation_2 = MathTex("v", "=", "w^{-1}")
        equation_2.scale(2)
        equation_3 = MathTex("w", "\\times","w^{-1}", "=", "1")
        equation_3.shift(UP*2).scale(2)

        self.play(Write(equation_1), Write(equation_2))
        self.wait(2)
        self.play(FadeOut(equation_1[2]))

        self.play(*[
            Transform(
                equation_2.get_part_by_tex("w^{-1}"),
                equation_3.get_part_by_tex("w^{-1}")                
            )
        ] + [
            Transform(
                equation_1.get_part_by_tex(tex),
                equation_3.get_part_by_tex(tex)
            )
            for tex in ("w", "\\times","=", "1")
        ])
        self.wait(1)

我试图让equation_2中的w^{-1}飞到以前由equation_1的v所占据的位置并转换为equation_3，而equation_1中的"1“则从equation_3转换为w^{-1}，而不是试图进行替换转换。

如何将equation_1转换为equation_3并移动equation_1的"v“所占位置的w^{-1}？

Answer 1

在这种特殊情况下，使用TransformMatchingShapes的方法工作得相当好：

class Eq(Scene):
    def construct(self):
        equation_1 = MathTex("w", "\\times","v", "=", "1")
        equation_1.shift(UP*2).scale(2)
        equation_2 = MathTex("v", "=", "w^{-1}")
        equation_2.scale(2)
        equation_3 = MathTex("w", "\\times","w^{-1}", "=", "1")
        equation_3.shift(UP*2).scale(2)

        self.play(Write(equation_1), Write(equation_2))
        self.wait(2)
        self.play(FadeOut(equation_1[2]))

        self.play(
            TransformMatchingShapes(
                VGroup(equation_1[0:2], equation_1[3:], equation_2[2].copy()),
                equation_3,
            )
        )

如果您的形状不是唯一匹配的，那么请看一下TransformMatchingShapes的实现，有一种方法可以精确地将什么转换成什么。