
{{alias}}( p, a, b[, upper] )
    Computes the inverse of the lower incomplete beta function.

    In contrast to a more commonly used definition, the first argument is the
    probability `p` and the second and third arguments are `a` and `b`,
    respectively.

    By default, the function inverts the lower regularized incomplete beta
    function. To invert the upper function, set the `upper` argument to `true`.

    If provided `NaN` as any argument, the function returns `NaN`.

    If provided `p < 0` or `p > 1`, the function returns `NaN`.

    If provided `a <= 0` or `b <= 0`, the function returns `NaN`.

    Parameters
    ----------
    p: number
        Probability.

    a: number
        Second function parameter.

    b: number
        Third function parameter.

    upper: boolean (optional)
        Boolean indicating if the function should invert the upper tail of the
        incomplete beta function. Default: `false`.

    Returns
    -------
    y: number
        Function value.

    Examples
    --------
    > var y = {{alias}}( 0.2, 3.0, 3.0 )
    ~0.327
    > y = {{alias}}( 0.4, 3.0, 3.0 )
    ~0.446
    > y = {{alias}}( 0.4, 3.0, 3.0, true )
    ~0.554
    > y = {{alias}}( 0.4, 1.0, 6.0 )
    ~0.082
    > y = {{alias}}( 0.8, 1.0, 6.0 )
    ~0.235
    > y = {{alias}}( NaN, 1.0, 1.0 )
    NaN
    > y = {{alias}}( 0.5, NaN, 1.0 )
    NaN
    > y = {{alias}}( 0.5, 1.0, NaN )
    NaN
    > y = {{alias}}( 1.2, 1.0, 1.0 )
    NaN
    > y = {{alias}}( -0.5, 1.0, 1.0 )
    NaN
    > y = {{alias}}( 0.5, -2.0, 2.0 )
    NaN
    > y = {{alias}}( 0.5, 0.0, 2.0 )
    NaN
    > y = {{alias}}( 0.5, 2.0, -2.0 )
    NaN
    > y = {{alias}}( 0.5, 2.0, 0.0 )
    NaN

    See Also
    --------

