Axes don't work correctly

[guiwenfeng]

I thought the y_axis center points should coincide with the dot, but now they don't

class Test(Scene):

    def setup(self):
        super().setup()
        self.axes_config = {
            "x_range": [0, 10],
            "y_range": [-2.5, 2.5, 0.25],
            "x_length": 10,
            "y_length": 7.5,
            "axis_config": {
                "stroke_width": 2,
            },
            "y_axis_config": {
                "include_tip": False,
                "numbers_to_include": [-2.0, -1.0, 0.0, 1.0, 2.0],
                "numbers_to_exclude": [],
                "decimal_number_config": {"num_decimal_places": 1},
            },
        }

    def construct(self):
        axes = Axes(**self.axes_config)
        y_axis = axes.y_axis

        self.add(axes)

        dot = Dot(ORIGIN, color=RED)
        self.add(dot)
        self.wait()

        y_axis.move_to(dot)
        self.wait()

        print(y_axis.get_center())
        print(dot.get_center())

https://github.com/user-attachments/assets/106aab2d-704f-4363-b9d9-84594bb5cd04

• macOS 11.7 (Big Sur)
• Python 3.8.16
• manim version v0.17.3

[uwezi]

I don't quite understand what you are intending to do here:

• should the dot be placed at the origin of the coordinate system first? Then you would need to use dot = Dot(axes.get_origin(), color=RED)
• or do you want to move the zero-point of the y-axis to the dot, then you need to shift by the difference between target position and current position. The default anchor point of an object like the y-axis is the center of mass of its surrounding bounding box.

class Test(Scene):

    def setup(self):
        super().setup()
        self.axes_config = {
            "x_range": [0, 10],
            "y_range": [-2.5, 2.5, 0.25],
            "x_length": 10,
            "y_length": 7.5,
            "axis_config": {
                "stroke_width": 2,
            },
            "y_axis_config": {
                "include_tip": False,
                "numbers_to_include": [-2.0, -1.0, 0.0, 1.0, 2.0],
                "numbers_to_exclude": [],
                "decimal_number_config": {"num_decimal_places": 1},
            },
        }

    def construct(self):
        axes = Axes(**self.axes_config)
        y_axis = axes.y_axis

        self.add(axes)

        dot = Dot(ORIGIN, color=RED)
        self.add(dot)
        self.wait()

        y_axis.shift(dot.get_center()-y_axis.n2p(0))
        self.wait()

        print(y_axis.get_center())
        print(dot.get_center())

https://github.com/user-attachments/assets/4770673e-6753-4a1b-b05c-4720477ba08c

[uwezi]

here is another short script highlighting the outlines and handles of an object like your y-axis

class Test2(Scene):

    def setup(self):
        super().setup()
        self.axes_config = {
            "x_range": [0, 10],
            "y_range": [-2.5, 2.5, 0.25],
            "x_length": 10,
            "y_length": 7.5,
            "axis_config": {
                "stroke_width": 2,
            },
            "y_axis_config": {
                "include_tip": False,
                "numbers_to_include": [-2.0, -1.0, 0.0, 1.0, 2.0],
                "numbers_to_exclude": [],
                "decimal_number_config": {"num_decimal_places": 1},
            },
        }

    def construct(self):
        axes = Axes(**self.axes_config)
        y_axis = axes.y_axis

        self.add(axes.set_opacity(0.7))
        for cp in [RIGHT,UR,UP,UL,LEFT,DL,DOWN,DR]:
            self.add(Dot(point=y_axis.get_critical_point(cp),radius=0.05,color=YELLOW))
        self.add(Dot(point=y_axis.get_center(),radius=0.05,color=TEAL))
        self.add(Dot(point=y_axis.n2p(0),radius=0.05,color=RED))
        self.add(SurroundingRectangle(y_axis, buff=0).set_fill(opacity=0).set_stroke(opacity=1,color=BLUE,width=1))

[guiwenfeng]

This is a demo, and when I was learning someone else's code, I found that the generated video was a little different from what I wanted, and I thought something might be wrong. Thank you very much for your reply, your reply perfectly solved my issue.