
{{alias}}( d1, d2 )
    Returns the standard deviation of an F distribution.

    If `d1 <= 0` or `d2 <= 4`, the function returns `NaN`.

    If `d1` or `d2` is `NaN`, the function returns `NaN`.

    Parameters
    ----------
    d1: number
        Numerator degrees of freedom.

    d2: number
        Denominator degrees of freedom.

    Returns
    -------
    out: number
        Standard deviation.

    Examples
    --------
    > var v = {{alias}}( 3.0, 5.0 )
    ~3.333
    > v = {{alias}}( 4.0, 12.0 )
    ~1.122
    > v = {{alias}}( 8.0, 5.0 )
    ~2.764

    See Also
    --------

