util.py 文件源码

def log_beta(t):
    """
    Computes log Beta function.

    :param t:
    :type t: torch.autograd.Variable of dimension 1 or 2
    :rtype: torch.autograd.Variable of float (if t.dim() == 1) or torch.Tensor (if t.dim() == 2)
    """
    assert t.dim() in (1, 2)
    if t.dim() == 1:
        numer = torch.sum(log_gamma(t))
        denom = log_gamma(torch.sum(t))
    else:
        numer = torch.sum(log_gamma(t), 1)
        denom = log_gamma(torch.sum(t, 1))
    return numer - denom