# Fixed Point Roll

A set of functions to operate over u64 numbers with 1e9 precision.

## Interface

### <mark style="color:blue;">roll</mark>

**It returns 1 ROLL - 1\_000\_000\_000.**&#x20;

```rust
public fun roll(): u64
```

* **@return u64**. 1e9

### <mark style="color:blue;">try\_mul\_down</mark>

**It tries to `x` \* `y` / 1\_000\_000\_000 rounding down. It returns zero instead of throwing an overflow error.**

```rust
public fun try_mul_down(x: u64, y: u64): (bool, u64)
```

* **@param x:** The first operand.
* **@param y:** The second operand.
* **@return bool.** If the operation was successful.
* **@return u64.** The result of `x` \* `y` / **1\_000\_000\_000**.

### <mark style="color:blue;">try\_mul\_up</mark>

**It tries to `x` \* `y` / 1\_000\_000\_000 rounding up. It returns zero instead of throwing an overflow error.**

```rust
public fun try_mul_up(x: u64, y: u64): (bool, u64)
```

* **@param x:** The first operand.
* **@param y:** The second operand.
* **@return bool.** If the operation was successful.
* **@return u64.** The result of `x` \* `y` / **1\_000\_000\_000**.

### <mark style="color:blue;">try\_div\_down</mark>

**It tries to `x` \* 1\_000\_000\_000 / `y` rounding down. It returns zero instead of throwing an overflow error.**

```rust
public fun try_div_down(x: u64, y: u64): (bool, u64)
```

* **@param x:** The first operand.
* **@param y:** The second operand.
* **@return bool.** If the operation was successful.
* **@return u64.** The result of **`x` \* 1\_000\_000\_000 / `y`**.

### <mark style="color:blue;">try\_div\_up</mark>

**It tries to `x` \* 1\_000\_000\_000 / `y` rounding up. It returns zero instead of throwing an overflow error.**

```rust
public fun try_div_up(x: u64, y: u64): (bool, u64)
```

* **@param x:** The first operand.
* **@param y:** The second operand.
* **@return bool.** If the operation was successful.
* **@return u64.** The result of **`x` \* 1\_000\_000\_000 / `y`**.

### <mark style="color:blue;">mul\_down</mark>

`x` \* `y` / **1\_000\_000\_000** rounding down.

```rust
public fun mul_down(x: u64, y: u64): u64
```

* **@param x:** The first operand.
* **@param y:** The second operand.
* **@return u64.** The result of `x` \* `y` / **1\_000\_000\_000**.

**Aborts**

* On overflow. If the result is over the maximum u256 number.

### <mark style="color:blue;">mul\_up</mark>

`x` \* `y` / **1\_000\_000\_000** rounding up.

```rust
public fun mul_up(x: u64, y: u64): u64
```

* **@param x:** The first operand.
* **@param y:** The second operand.
* **@return u64.** The result of `x` \* `y` / **1\_000\_000\_000**.

**Aborts**

* On overflow. If the result is over the maximum u256 number.

### <mark style="color:blue;">div\_down</mark>

`x` \*  **1\_000\_000\_000** / `y` rounding down.

```rust
public fun div_down(x: u64, y: u64): u64
```

* **@param x:** The first operand.
* **@param y:** The second operand.
* **@return u64.** The result of `x` \*  **1\_000\_000\_000** / `y`.

**Aborts**

* On zero division.

### <mark style="color:blue;">div\_up</mark>

`x` \*  **1\_000\_000\_000** / `y` rounding up.

```rust
public fun div_up(x: u64, y: u64): u64
```

* **@param x:** The first operand.
* **@param y:** The second operand.
* **@return u64.** The result of `x` \*  **1\_000\_000\_000** / `y`.

**Aborts**

* On zero division.

### <mark style="color:blue;">to\_roll</mark>

**It converts `x` precision to a `ROLL`, a number with a precision of 1e9.**

```rust
public fun to_roll(x: u64, decimal_factor: u64): u64
```

* **@param x:** The value to be converted.
* **@param decimal\_factor:** The current decimal scalar of x.&#x20;
* **@return u64.** The result of `x` \*  **1\_000\_000\_000** / `y`.

**Aborts**

* decimal\_factor is zero.