loc: label-based (or boolean array) -> 이름 기준
loc[행 인덱싱 값, 열 인덱싱 값]
loc['2020-04-09', 'column_name']
## multiple conditions
df.loc[
(df.Humidity > 50) & (df.Weather == 'Shower'),
['Temperature','Wind'],
]iloc: integer postion-based (or boolean array) -> 순서(인덱스) 기준
iloc[row_postion, column_position]
# Getting ValueError
df.iloc[df.Humidity > 50, :] # error
# Single condition
df.iloc[list(df.Humidity > 50)]
