我正在弄清楚哪个 python 库最适合计算技术指标。在使用不同的库进行计算时，我得到了以下结果。我不知道我是否计算ema错误。不同方法的结果不匹配。哪个是正确的方法？
代码 ：
#calculating ema using tulipy library
ask = df['askclose'].values
df['tulipy'] = (tulipy.ema(ask, period=9))
#calculating ema using pandas library
df['pandas'] = df['askclose'].ewm(span=9,min_periods=0,adjust=False,ignore_na=False).mean()
#calculating ema using TA-Lib library
df['ta-lib'] = talib.EMA(df['askclose'],timeperiod=9)
#calculating ema using pyti library
df['pyti'] = pyti.exponential_moving_average.exponential_moving_average(df['askclose'], period=9)
print(df[['askclose','tulipy','pandas','ta-lib','pyti']].head(20))
输出数据框：
| 日期 | 问关闭 | 郁金香 | 熊猫 | 塔库 | 皮蒂 |
|---|---|---|---|---|---|
| 2020-12-18 00:00:00 | 1.35702 | 1.357020 | 1.357020 | 钠 | 钠 |
| 2020-12-18 00:01:00 | 1.35707 | 1.357030 | 1.357030 | 钠 | 钠 |
| 2020-12-18 00:02:00 | 1.35689 | 1.357002 | 1.357002 | 钠 | 钠 |
| 2020-12-18 00:03:00 | 1.35697 | 1.356996 | 1.356996 | 钠 | 钠 |
| 2020-12-18 00:04:00 | 1.35711 | 1.357018 | 1.357018 | 钠 | 钠 |
| 2020-12-18 00:05:00 | 1.35711 | 1.357037 | 1.357037 | 钠 | 钠 |
| 2020-12-18 00:06:00 | 1.35712 | 1.357053 | 1.357053 | 钠 | 钠 |
| 2020-12-18 00:07:00 | 1.35720 | 1.357083 | 1.357083 | 钠 | 钠 |
| 2020-12-18 00:08:00 | 1.35711 | 1.357088 | 1.357088 | 1.357067 | 1.357099 |
| 2020-12-18 00:09:00 | 1.35713 | 1.357097 | 1.357097 | 1.357079 | 1.357108 |
| 2020-12-18 00:10:00 | 1.35694 | 1.357065 | 1.357065 | 1.357051 | 1.357071 |
| 2020-12-18 00:11:00 | 1.35697 | 1.357046 | 1.357046 | 1.357035 | 1.357053 |
| 2020-12-18 00:12:00 | 1.35701 | 1.357039 | 1.357039 | 1.357030 | 1.357046 |
| 2020-12-18 00:13:00 | 1.35705 | 1.357041 | 1.357041 | 1.357034 | 1.357045 |
| 2020-12-18 00:14:00 | 1.35696 | 1.357025 | 1.357025 | 1.357019 | 1.357023 |
| 2020-12-18 00:15:00 | 1.35700 | 1.357020 | 1.357020 | 1.357015 | 1.357015 |
| 2020-12-18 00:16:00 | 1.35693 | 1.357002 | 1.357002 | 1.356998 | 1.356989 |
| 2020-12-18 00:17:00 | 1.35688 | 1.356978 | 1.356978 | 1.356975 | 1.356960 |
| 2020-12-18 00:18:00 | 1.35692 | 1.356966 | 1.356966 | 1.356964 | 1.356946 |
| 2020-12-18 00:19:00 | 1.35691 | 1.356955 | 1.356955 | 1.356953 | 1.356938 |