Cycle from one to zero and back?

Question

Algorithms

I make an animation when the element moves to one side and repels from it and returns, etc. infinite...
I can't implement the change of values ​​on the border,

[1, 0.9, 0.8, ..., 0.2, 0.1, 0, 0.1, 0.2, ...1..0....

Answer 1

Brought you the metacode.

start = 0 // откуда вы начинаете
stop = 1 // куда вы движетесь

step = 0.1 // шаг, с которым вы движетесь

position = 0 // ваше текущее положение

while (true) { // чтобы анимация всегда повторялась, цикл должен быть вечным
  position = position + step // приращиваем наш шаг

  if (position == start || position == stop) { 
               // как только мы достигаем границы
               // меняем знак шага, то есть меняем направление движения
    step = -step
  }
}

This example has only one drawback.
The start point must always be less than the end point.
If you have the opposite, change the sign of the step at the beginning.

Answer 2

Discover the operation of taking the remainder of the division (mod), with the help of this operation it is achieved twice. Example .

Answer 3

The first thought is this:

while(true){
showToOne();
showToZero();
}

void showToOne(){
//
}

void showToZero(){
//
}

or you can add recursive calls.

Answer 4

while True:
for i in range(0, 1.1, 0.1):
print(i)
for i in range(1, -0.1, -0.1):
print(i)

Answer 5

while(true) y=0,5+0,5*F(x++);
where F(t) - any periodic function that defines the animation,
0.5+0.5*F(t) - offset for the range [0;1].
For example, pendulum swings have a sinusoidal animation F(t) = Sin(t);
uniform shift per step - triangular shape of the animation curve.
List of the most common forms of curved animations (transitions): https://ru.wikipedia.org/wiki/waveform .