# Resetting the state of a Quaternion

[Русская версия / Russian version](reset-rus.md)

Function for **BGC_FP32_Quaternion**:

```c
inline void bgc_fp32_quaternion_reset(BGC_FP32_Quaternion* const quaternion);
```

Function for **BGC_FP64_Quaternion**:

```c
inline void bgc_fp64_quaternion_reset(BGC_FP64_Quaternion* const quaternion);
```

These functions set all the components of a quaternion to zero.

Each of these functions is equivalent to the following lines of code:

```c
vector->s = 0;
vector->x = 0;
vector->y = 0;
vector->z = 0;
```

This function is good for setting up the initial state of a quaternion.

### Parameter

| Parameter  | Direction | Description                                                  |
| ---------- | --------- | ------------------------------------------------------------ |
| quaternion |    out    | A pointer to a quaternions which components must be set to 0 |

You should pass only valid pointers in the parameter *quaternion*. The NULL (0) value is considered invalid.

### Example

```c
#include <stdio.h>
#include <basic-geometry.h>

int main()
{
    BGC_FP64_Quaternion q;

    bgc_fp64_quaternion_reset(&q);

    printf("s = %lf, x = %lf, y = %lf, z = %lf\n", q.s, q.x, q.y, q.z);

    return 0;
}
```

[Documentation](../intro-eng.md) / [Quaternions](../quaternion-eng.md)