類型錯誤：strptime() 參數 1 必須是 str，而不是句點

Question

我有這個數據框。

import pandas as pd
from datetime import datetime
df = pd.DataFrame({'id': [11,22,33,44,55], 
                   'name': ['A','B','C','D','E'], 
                   'timestamp': [1407617838,965150022,1158531592,1500701864,965149631]})

df
   id name timestamp
0  11    A      2014
1  22    B      2000
2  33    C      2006
3  44    D      2017
4  55    E      2000

df['timestamp'] = pd.to_datetime(df['timestamp'], unit='s')
df['timestamp'] = df['timestamp'].dt.to_period('Y')
y1 = df['timestamp'].iloc[0]
y2 = df['timestamp'].iloc[1]
d1 = datetime.strptime(y1, "%Y")
d2 = datetime.strptime(y2, "%Y")
diff = abs((d2 - d1).days)
print(diff)

我已將時間戳轉換為實際日期並獲取年份。 我想要兩個時間戳的前兩行之間的差異。 例如 (abs (2014-2000) = 4)

Answer 1

如果您通過timeseries的dt 訪問器獲取年份，則會得到整數（而不是“Period”對象）：

df['timestamp'] = pd.to_datetime(df['timestamp'], unit='s')
df['timestamp'] = df['timestamp'].dt.year
y1 = df['timestamp'].iloc[0]
y2 = df['timestamp'].iloc[1]
# d1 = datetime.strptime(y1, "%Y") <- No need to recast to datetime!
# d2 = datetime.strptime(y2, "%Y")
diff = abs((y2 - y1))
print(diff)
>>> 14

如您所見，我評論了這兩行是您試圖將年份重新轉換為datetime對象。 這有什么原因嗎？ 根據您的問題，我假設您想要年數的差異。 如果您想要時間戳之間的確切天數，則應該這樣做：（無需轉換和重新轉換）：

df['timestamp'] = pd.to_datetime(df['timestamp'], unit='s')
y1 = df['timestamp'].iloc[0]
y2 = df['timestamp'].iloc[1]
diff = abs((y2 - y1).days)
print(diff)
>>> 5122