> ## Documentation Index
> Fetch the complete documentation index at: https://docs.magickml.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Float

# ACOS (math/acos/float)

The ACOS node calculates the inverse cosine (arccos) of a given float input. It returns the angle in radians whose cosine is the input value.

## Inputs

1. `a` (float, default: 0): The input value for which to calculate the inverse cosine. The value should be between -1 and 1, inclusive.

## Outputs

1. `result` (float): The angle in radians whose cosine is the input value. The output range is between 0 and π (pi), inclusive.

## Configuration

This node has no configuration options.

## Usage

To use the ACOS node, follow these steps:

1. Add the ACOS node to your spell.
2. Connect a float value between -1 and 1 to the `a` input port.
3. The node will output the inverse cosine of the input value in radians through the `result` output port.

## Example

Here's an example of how to use the ACOS node in a spell:

```json theme={null}
{
  "nodes": [
    {
      "type": "math/acos/float",
      "id": "acos_1",
      "inputs": {
        "a": 0.5
      }
    },
    {
      "type": "math/radiansToDegrees/float",
      "id": "radToDeg_1",
      "inputs": {
        "radians": "@acos_1.result"
      }
    },
    {
      "type": "io/print/float",
      "id": "print_1",
      "inputs": {
        "value": "@radToDeg_1.degrees"
      }
    }
  ]
}
```

In this example:

1. The ACOS node (`acos_1`) takes an input value of 0.5 and calculates its inverse cosine.
2. The result is passed to the `radiansToDegrees` node (`radToDeg_1`), which converts the angle from radians to degrees.
3. Finally, the `print` node (`print_1`) outputs the angle in degrees.

The expected output would be approximately 60 degrees, as the inverse cosine of 0.5 is roughly 1.0472 radians or 60 degrees.

## Best Practices and Tips

* Ensure that the input value is within the valid range of -1 to 1. Inputting values outside this range will result in NaN (Not a Number) as the output.
* Remember that the output is in radians. If you need the result in degrees, use a `radiansToDegrees` node to convert the output.

## Common Issues

* If the input value is outside the range of -1 to 1, the output will be NaN. Make sure to validate or clamp the input value before connecting it to the ACOS node.
* Be mindful of the units (radians or degrees) when working with angles in your spell. Inconsistent units can lead to unexpected results.