为什么我收到关于“字符串索引必须是整数”的错误？

Question

我希望通过计算唯一的屏幕名称来查找玩家总数。     #Dependencies     将pandas导入为pd

# Save path to data set in a variable
df = "purchase_data.json"

# Use Pandas to read data
data_file_pd = pd.read_json(df)
data_file_pd.head()

# Find total numbers of players
player_count = len(df['SN'].unique())

TypeError                                 Traceback (most recent call last)
<ipython-input-26-94bf0ee04d7b> in <module>()
  1 # Find total numbers of players
----> 2 player_count = len(df['SN'].unique())

TypeError: string indices must be integers

Answer 1

无法访问原始数据，这是猜测工作。但我想你可能想要这样的东西：

# Save path variable (?)
json_data = "purchase_data.json"

# convert json data to Pandas dataframe
df = pd.read_json(json_data)
df.head()
len(data_file_pd['SN'].unique())

Answer 2

很简单，如果您在连接架构时遇到此错误。然后在那时关闭 Web 浏览器并杀死 Pg 管理服务器并重新启动它。那么它就会完美运行