一日を15分刻みにした1次元配列で取り扱う
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import datetime
import pandas as pd
timestamp_index = []
timestamp_list = [0]*24*4
for val1 in range(0, 24,1):
for val2 in [0,15,30, 45]:
timestamp_index.append('{0:02d}:{1:02d}'.format(val1, val2))
df = pd.DataFrame(timestamp_list, index=time_stamp_index, columns=['counts'])
timestamp = datetime.datetime.strptime('2020/1/1 11:43:00', '%Y/%m/%d %H:%M:%S' )
idx = timestamp.hour*4 + int(timestamp.minute / 15)
df.iloc[idx] += 1
df.iloc[idx]
