有停牌时，排序值好像不符合预期。

[qtbgo]

请教，针对A股运行如下代码

`from spectre.data import ArrowLoader
import torch
from spectre.factors import *
from spectre.factors.basic import *

loader = ArrowLoader('./Ashare.feather')

engine = FactorEngine(loader)
if torch.cuda.is_available():
print("GPU is available.")
engine.to_cuda()
else:
print("GPU is not available.")
engine.to_cpu()

universe = StaticAssets({'SZ002880','SH600030'}) # 5.29日SZ002880停牌
engine.set_filter(universe) # 设置股池
engine.add(RankFactor(inputs=[OHLCV.close]), 'RankFactor')
all_factors = engine.run("2023-5-25", "2023-5-29")
print(all_factors)

输出`结果如下，29号SZ002880停牌，所以只有SH600030，期望其排序值为1，为啥输出的是2呢？
RankFactor
date asset
2023-05-26 00:00:00+00:00 SH600030 2.0
SZ002880 1.0
2023-05-29 00:00:00+00:00 SH600030 2.0

[qtbgo]

经过测试，发现对每一天，若股池中有一只股票停牌，则股票排名从2开始，若有2只股票停牌，则排名从3开始，以此类推。