7f6cd7f219c8c7f77b8e49e92f26ffae9229d698,src/math_util.py,,logsumexp,#Any#,53

Before Change

def logsumexp(array):
    m = max(array)
    if m == float("inf"):
        return float("inf")
    elif m == -float("inf"):
        return -float("inf")

After Change

    // m = -inf means addends are all zero, hence so is sum, and log is
    // -inf.  But if +inf and -inf are among the inputs, or if input is
    // NaN, let the usual computation yield a NaN.
    if math.isinf(m) and min(array) != -m and \
       all(not math.isnan(a) for a in array):
        return m

    // Since m = max{a_0, a_1, ...}, it follows that a <= m for all a,
    // so a - m <= 0; hence exp(a - m) is guaranteed not to overflow.
    return m + math.log(sum(math.exp(a - m) for a in array))

def logmeanexp(array):
    inf = float("inf")

Instances