将日期时间对象按小时排序到Pandas数据框,然后使用Matplotlib可视化为直方图
我需要按小时将观看者分类为直方图.我有一些使用Matplotlib进行操作的经验,但是我找不到按小时对日期进行排序最实用的方法.
I need to sort viewers by hour to a histogram. I have some experience using Matplotlib to do that, but I can't find out what is the most pragmatic way to sort the dates by hour.
首先,我从JSON文件中读取数据,然后将两种相关的数据类型存储在pandas Dataframe中,如下所示:
First I read the data from a JSON file, then store the two relevant datatypes in a pandas Dataframe, like this:
data = pd.read_json('data/data.json')
session_duration = pd.to_datetime(data.session_duration, unit='s').dt.time
time = pd.to_datetime(data.time, format='%H:%M:%S').dt.time
viewers = []
for x, y in zip(time, session_duration):
viewers.append({str(x):str(y)})
源文件看起来像这样,而忽略了不相关的部分.
The source file looks like this, leaving out the irrelevant parts.
{
"time": "00:00:09",
"session_duration": 91
},
{
"time": "00:00:16",
"session_duration": 29
},
{
"time": "00:00:33",
"session_duration": 102
},
{
"time": "00:00:35",
"session_duration": 203
}
请注意,session_duration以秒为单位.
Note that the session_duration is in seconds.
我必须区分两种类型的观众:
I have to distinguish two types of viewers:
- 在视频流上花费了< = 1分钟的人
- 在流中花费> = 1分钟的人
为此,我这样做:
import datetime
for element in viewers:
for time, session_duration in element.items():
if datetime.strptime(session_duration, '%H:%M:%S').time() >= datetime.strptime('00:01:00', '%H:%M:%S').time():
viewers_more_than_1min.append(element)
else:
viewers_less_than_1min.append(element)
结果,我将值存储在这样的字典中:{session_duration:time} 其中键是会话结束的时间流,而值是观看时间.
As a result I have my values in a dictionary like this: {session_duration:time} Where the key is the time when the session ended the stream and the value is the time spent watching.
[{'00:00:09': '00:01:31'},
{'00:00:16': '00:00:29'},
{'00:00:33': '00:01:42'},
{'00:00:35': '00:03:23'},
{'00:00:36': '00:00:32'},
{'00:00:37': '00:04:47'},
{'00:00:47': '00:00:42'},
{'00:00:53': '00:00:44'},
{'00:00:56': '00:00:28'},
{'00:00:58': '00:01:17'},
{'00:01:04': '00:01:16'},
{'00:01:09': '00:00:46'},
{'00:01:29': '00:01:07'},
{'00:01:31': '00:01:02'},
{'00:01:32': '00:01:01'},
{'00:01:32': '00:00:36'},
{'00:01:37': '00:03:03'},
{'00:01:49': '00:00:57'},
{'00:02:01': '00:02:15'},
{'00:02:18': '00:01:16'}]
作为最后一步,我希望创建一个带有Matplotlib的直方图,该直方图表示每小时从上述两种查看器类型获得的每个观看者人数.我认为它会像这样:
As a final step I wish to create a histogram withMatplotlib representing the viewercount for each our from the two viewertypes mentioned above per hour. I assume it would go something like this:
import matplotlib.pyplot as plt
import datetime as dt
hours = [(dt.time(i).strftime('%H:00')) for i in range(24)]
plt.xlabel('Hour')
plt.ylabel('Viewer count')
plt.bar(hours, sorted_viewcount_byhour)
df = pd.read_json('data/data.json')
df['time'] = pd.to_datetime(df['time'])
#timedelta is a more appropriate data type for session_duration
df['session_duration'] = pd.to_timedelta(df['session_duration'], unit='s')
# Example filtering
df_short_duration = df[df['session_duration'].dt.total_seconds() <= 60]
# Example creating histogram
df_hist = df_short_duration.groupby(df['time'].dt.hour).count()
# Now just plot df_hist as a bar chart using matplotlib, might be something like plt.bar(df_hist.index, df_hist['count'])