How Manim create a pendulum video with a few lines of code | with source code

This article records how I created a Modular Arithmetic Multiplication Animation using manim.

the video is requiring below a few items.

1. totally 120 balls are there, totally 5 mins duration.
2. good quaility, 4K with 60 FPS

from manim import *
import numpy as np
from os import system
import math

config.media_dir = "E:\PythonMedia\media"
config.frame_width = 16#9#16
config.frame_height = 9#16#
config.frame_size = (3840,2160)#(720,1280)#(2160,3840)##(3840,2160)##(3840,2160)#(1280,720)#(1080, 1920) #(1920, 1080) 426 x , 640 x 360,
config.frame_rate = 60
config.background_color = BLACK
class No32_purePendulum(Scene):
    frameIndex = 0
    frameIndexBook = []
    ballPlay = []
    fristFewCount = 15
    def construct(self):
        count = 120
        runTime = 300
        radius_ = np.linspace(0.5,4.2, count)
        circles = [Circle(radius=_, fill_opacity=0, stroke_width=1, stroke_color=BLACK).rotate(PI/2)
                   for _ in radius_]
        positions = [np.linspace(0, count-_, runTime*config.frame_rate) for _ in range(count)]
        print(positions)
        print("------------")
        print(len(positions[0]))
        def update_collection():
            vg = VGroup()

            for index in range(count-1):
                if self.frameIndex<=10 or self.frameIndex >= len(positions[0])-1:
                    s_ = circles[index].point_from_proportion(0)
                    e_ = circles[index + 1].point_from_proportion(0)
                else:
                    s_ = round(positions[index][self.frameIndex], 3) - math.floor(positions[index][self.frameIndex])
                    s_ = circles[index].point_from_proportion(s_)

                    e_ = round(positions[index + 1][self.frameIndex], 3) - math.floor(
                        positions[index + 1][self.frameIndex])
                    e_ = circles[index + 1].point_from_proportion(e_)
                line = Line(start=s_, end=e_, stroke_color=WHITE, stroke_width=1)
                vg.add(line)
            #print(self.frameIndex)
            self.frameIndex = self.frameIndex + 1

            return vg

        objects = always_redraw(update_collection)
        self.add(objects)

        self.play(Create(Text("").move_to(LEFT * 100), run_time=(runTime*config.frame_rate + 3) / config.frame_rate,
                         rate_func=linear)) #(runTime*config.frame_rate + 3) / config.frame_rate
if __name__ == '__main__':
    system("manim -ql {} No32_purePendulum --disable_caching".format(__file__))