model.py 文件源码

def log_sum_exp(input, keepdim=False):
    assert input.dim() == 2
    max_scores, _ = input.max(dim=-1, keepdim=True)
    output = input - max_scores.expand_as(input)
    return max_scores + torch.log(torch.sum(torch.exp(output), dim=-1, keepdim=keepdim))