import numpy as np
import pandas as pd
import matplotlib.pyplot as plt
from datetime import datetime
# 2019년 1월 24일
today = datetime(2019,1,24)
# 0시, 0분 디폴트값
today
datetime.datetime(2019, 1, 24, 0, 0)
# 시,분,초 지정
today = datetime(2019,1,24,13,39)
today
datetime.datetime(2019, 1, 24, 13, 39)
today.day
24
today.hour
13
# datetime 객체로 list 생성 예시
dates = [datetime(2019,1,23), datetime(2019,1,24)]
# 인덱스 전환
dt_index = pd.DatetimeIndex(dates)
dt_index
DatetimeIndex(['2019-01-23', '2019-01-24'], dtype='datetime64[ns]', freq=None)
# 랜덤 데이터를 생성하고 인덱스와 함께 DataFrame 만들기
data = np.random.randn(2,2)
cols = ['A','B']
df = pd.DataFrame(data=data, index=dt_index, columns=cols)
df
A | B | |
---|---|---|
2019-01-23 | -1.093658 | 0.300429 |
2019-01-24 | 1.217856 | 0.792852 |
df.index
DatetimeIndex(['2019-01-23', '2019-01-24'], dtype='datetime64[ns]', freq=None)
# Latest Date Location
df.index.argmax()
1
df.index.max()
Timestamp('2019-01-24 00:00:00')
# Earliest Date Location
df.index.argmin()
0
df.index.min()
Timestamp('2019-01-23 00:00:00')