在Python中從pandas DataFrame提取數據

Question

這是我擁有的DataFrame的示例，我想根據每個時間范圍提取“ totalCount”的相應數據。

df = [{"username": "last",
"time_data": "{\"hours\":[{\"hour\":\"00:00\",\"postCount\":\"5\",\"topicCount\":\"3\",\"totalCount\":80},{\"hour\":\"01:00\",\"postCount\":\"11\",\"topicCount\":\"6\",\"topciCount\":31}"
},
{"username": "truk",
 "time_data": "{\"hours\":[{\"hour\":\"00:00\",\"postCount\":\"11\",\"topicCount\":\"6\",\"totalCount\":362},{\"hour\":\"01:00\",\"postCount\":\"22\",\"topicCount\":\"8\",\"topicCount\":355}"
}]
df = pd.DataFrame(df)
df

我已經使用此代碼來獲取“ 00:00”和“ 01:00”的“ postCount”：

df_h0 = df.copy()
df_h0['hour']='00:00'
df_h0['totalCount']=df.time_data.str.split('"00:00","postCount":"').str[1].str.split('","topic').str[0]
df_h0 = df_h0.fillna(0)

df_h1 = df.copy()
df_h1['hour']='01:00'
df_h1['totalCount']=df.time_data.str.split('"01:00","postCount":"').str[1].str.split('","topic').str[0]
df_h1 = df_h1.fillna(0)

df_tot = df_h0.append([df_h1])
df_tot.head()

但是現在我想獲取的“ totalCount”不僅僅在小時數旁邊。 有人知道該怎么做嗎？

預期產量：

                           time_data                 username   hour    totalCount
0   {"hours":[{"hour":"00:00","postCount":"5","top...   last    00:00   80
1   {"hours":[{"hour":"00:00","postCount":"11","to...   truk    00:00   362
0   {"hours":[{"hour":"00:00","postCount":"5","top...   last    01:00   31
1   {"hours":[{"hour":"00:00","postCount":"11","to...   truk    01:00   355

Answer 1

要解決此問題，您應該制作一個正則表達式以將文本提取到正確的位置。 但這不是解決問題的正確方法。 理想情況下，為了充分利用DataFrame結構，應該將接收到的數據解析為DataFrame列，以便可以使用更方便，更高效的方法：

totals_over_one_hundred = df.loc[df['totalCount'] > 100]