{{alias}}( x )
    Converts an angle from degrees to radians.

    Parameters
    ----------
    x: number
        Angle in degrees.

    Returns
    -------
    r: number
        Angle in radians.

    Examples
    --------
    > var r = {{alias}}( 90.0 )
    ~1.571
    > r = {{alias}}( -45.0 )
    ~-0.785
    > r = {{alias}}( NaN )
    NaN

    See Also
    --------