- Calculates the sine of an angle.

`angle`-
- The angle, using a full circle range of 0.0-1.0 measured clockwise (0.0 to the right).

The `sin()`

function calculates the sine of an angle.

PICO-8 uses an input range of 0.0 to 1.0 to represent the angle, a percentage of the unit circle. Some refer to these units as "turns". For instance, 180° or π (3.14159) radians corresponds to 0.5 turns in PICO-8's representation of angles. In fact, for fans of τ (tau), it's just a matter of dropping τ from your expression.

**Important:** PICO-8 measures the angle in a *clockwise* direction on the Cartesian plane, with 0.0 to the right, 0.25 downward, and so on. This is inverted from the convention used in traditional geometry, though the inversion only affects `sin()`

, not `cos()`

.

The inversion is useful because PICO-8's screen (like most graphics engines) uses inverted y coordinates: an increase in y goes downward. Many uses of `sin()`

would need to be inverted anyway, so PICO-8 does it by convention.

(The clockwise direction of the angle is equivalent to going counterclockwise and negating `sin()`

. This is how it is described in the official documentation.)

## Examples[edit | edit source]

```
for t=0,1,0.125 do
print('sin('..t..') = '..sin(t))
end
```

prints:

sin(0) = 0 sin(0.125) = -0.7071 sin(0.25) = -1 sin(0.375) = -0.7071 sin(0.5) = 0 sin(0.625) = 0.7071 sin(0.75) = 1 sin(0.875) = 0.7071 sin(1) = 0