def _compute_rdp()

in opacus/accountants/analysis/rdp.py [0:0]

• 11 lines of code
• 5 McCabe index (conditional complexity)

def _compute_rdp(q: float, sigma: float, alpha: float) -> float:
    r"""Computes RDP of the Sampled Gaussian Mechanism at order ``alpha``.

    Args:
        q: Sampling rate of SGM.
        sigma: The standard deviation of the additive Gaussian noise.
        alpha: The order at which RDP is computed.

    Returns:
        RDP at order ``alpha``; can be np.inf.
    """
    if q == 0:
        return 0

    # no privacy
    if sigma == 0:
        return np.inf

    if q == 1.0:
        return alpha / (2 * sigma ** 2)

    if np.isinf(alpha):
        return np.inf

    return _compute_log_a(q, sigma, alpha) / (alpha - 1)