{{alias}}( x, y )
    Computes the cosine of a number on `[-π/4, π/4]`.

    For increased accuracy, the number for which the cosine should be evaluated
    can be supplied as a double-double number (i.e., a non-evaluated sum of two
    double-precision floating-point numbers `x` and `y`).

    The two numbers must satisfy `|y| < 0.5 * ulp( x )`.

    If either argument is `NaN`, the function returns `NaN`.

    Parameters
    ----------
    x: number
        Input value (in radians).

    y: number
        Tail of `x`.

    Returns
    -------
    out: number
        Cosine.

    Examples
    --------
    > var out = {{alias}}( 0.0, 0.0 )
    ~1.0
    > out = {{alias}}( {{alias:@stdlib/constants/float64/pi}}/6.0, 0.0 )
    ~0.866
    > out = {{alias}}( 0.785, -1.144e-17 )
    ~0.707
    > out = {{alias}}( NaN )
    NaN

    See Also
    --------