# \[SOLVED\] Code not working for a strange reason

**URL:** <https://discourse.processing.org/t/solved-code-not-working-for-a-strange-reason/7030>\
**Category:** Coding Questions\
**Created:** [December 30, 2018, 10:10pm UTC](https://discourse.processing.org/t/solved-code-not-working-for-a-strange-reason/7030 "2018-12-30T22:10:54Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![bilo](https://avatars.discourse-cdn.com/v4/letter/b/3da27b/32.png) [@bilo](https://discourse.processing.org/u/bilo)\
**Post date:** [December 30, 2018, 10:10pm UTC](https://discourse.processing.org/t/solved-code-not-working-for-a-strange-reason/7030/1 "2018-12-30T22:10:54Z")

</div>

i have wrote a simple code that supposed to make a ball bounce aroud the screen so what`s happening is that the if,elseif and else statment are getting followed in the case of the width but not the heigth

if someone can copy the code into processing an figure out the problem it would be appreciated  
the code:

```auto
float circleX = 0;
float circleY = 180;
float xChanger = 0;
float yChanger = 0;

void setup() {
  size(640, 360);
}

void draw() {
  background(50);
  fill(250);
  ellipse(circleX, circleY, 24, 24);
  if (circleX == width) {
    xChanger = -5;
    yChanger = -2.8;
    println("x = 640");
  } else if (circleY == 0) {
    xChanger = -5;
    yChanger = 2.8;
    println("y = 0");
  } else if (circleX == 0) {
    xChanger = 5;
    yChanger = 2.8;
    println("x = 0");
  } else if (circleY == height) {
    xChanger = 5;
    yChanger = -2.8;
    println("y = 360");
  }

  circleX = circleX + xChanger;
  circleY = circleY + yChanger;
}

```

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<div class="post-metadata">

**Author:** ![Architector\_4](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/architector_4/32/813_2.png) [@Architector\_4](https://discourse.processing.org/u/Architector_4)\
**Post date:** [December 30, 2018, 11:08pm UTC](https://discourse.processing.org/t/solved-code-not-working-for-a-strange-reason/7030/2 "2018-12-30T23:08:59Z")

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The problem is the statements inside of your `if` statements.

For example, let’s look at `if (circleY == height) ...` and what it does as `circleY` changes over time.  
So, let’s assume that `yChanger` is 2.8.

The last statement inside `draw()` changes `circleY` every single time. So, it sets it from `0` to `2.8`, then to `5.6`, then to `8.3`, `11.2`, `14.0`, …, `355.6`, `358.4`, `361.2`…

In other words, with `2.8` added to `circleY`, it jumps from `358.4` to `361.2` and then grows ever bigger, and is never equal to exactly `360`.

The solution for this is to use “less than or equal” or “more than or equal” comparisons, instead of just equal, i.e. `>=` and `<=` instead of just `==`.

Here’s your code with that solution in place:

```auto
float circleX = 0;
float circleY = 180;
float xChanger = 0;
float yChanger = 0;

void setup() {
size(640, 360);
}

void draw() {
background(50);
fill(250);
ellipse(circleX, circleY, 24, 24);
if (circleX >= width) {
xChanger = -5;
yChanger = -2.8;
println(“x = 640”);
} else if (circleY <= 0) {
xChanger = -5;
yChanger = 2.8;
println(“y = 0”);
} else if (circleX <= 0) {
xChanger = 5;
yChanger = 2.8;
println(“x = 0”);
} else if (circleY >= height) {
xChanger = 5;
yChanger = -2.8;
println(“y = 360”);
}

circleX = circleX + xChanger;
circleY = circleY + yChanger;
}

```

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<div class="post-metadata">

**Author:** ![bilo](https://avatars.discourse-cdn.com/v4/letter/b/3da27b/32.png) [@bilo](https://discourse.processing.org/u/bilo)\
**Post date:** [December 30, 2018, 11:51pm UTC](https://discourse.processing.org/t/solved-code-not-working-for-a-strange-reason/7030/3 "2018-12-30T23:51:30Z")

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oh yeah i got it thank you for your help \<3