I have an error in my code the current error is a TypeError: 'NoneType' object is not subs-CodePudding

This is my current code,

import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
import requests
plt.style.use("fivethirtyeight")


df = pd.read_csv("TSLA.csv")
df = df.set_index(pd.DatetimeIndex(df["Date"].values))


ShortEMA = df.Close.ewm(span=5, adjust = False).mean()
MiddleEMA = df.Close.ewm(span = 21, adjust = False).mean()
LongEMA = df.Close.ewm(span = 53, adjust = False).mean()

df['Short'] = ShortEMA
df['Middle'] = MiddleEMA
df['Long'] = LongEMA

def MyStrat(data):
    bought_list = []
    sold_list = []
    current_pos = "None"
    for i in range(0, len(data)):
        if  data["Close"][i] > data["Short"][i] and current_pos == "None":
            bought_list.append(data["Close"][i])
            sold_list.append(np.nan)
            current_pos = "Bought"

        else:
            data["Close"][i] < data["Short"][i] and current_pos == "Bought"
            sold_list.append(data["Close"][i])
            bought_list.append(np.nan)
            current_pos = "None"

print(MyStrat(df)["Close"])
df["Bought"] = MyStrat(df)
df["Sold"] = MyStrat(df)

I get the error

File "c:\Users\zackz\Desktop\AlgoTrading.py", line 100, in <module>
print(MyStrat(df)["Close"])
TypeError: 'NoneType' object is not subscriptable

The data looks something like this,

    Date         Open         High          Low        Close    Adj Close    Volume        Short      Middle        Long

2021-04-01  2021-04-01   688.369995   692.419983   659.419983   661.750000   661.750000  35298400   661.750000  661.750000  661.750000
2021-04-05  2021-04-05   707.710022   708.159973   684.700012   691.049988   691.049988  41842800   671.516663  664.413635  662.835185
2021-04-06  2021-04-06   690.299988   696.549988   681.369995   691.619995   691.619995  28271800   678.217773  666.886941  663.901289
2021-04-07  2021-04-07   687.000000   691.380005   667.840027   670.969971   670.969971  26309400   675.801839  667.258125  664.163092
2021-04-08  2021-04-08   677.380005   689.549988   671.650024   683.799988   683.799988  23924300   678.467889  668.761931  664.890384

I just want to add the data from the code, when bought, when sold, into the last 2 columns in the data, then i will plot the data.

Thanks In Advance

CodePudding user response：

Your MyStrat function does not return anything, so you're basically trying to get the "Close" key from a None value. Try returning whatever you need from the MyStrat function at the end of the body.