Pandas 기초 5 (데이터프레임 행,열 삭제)

In [1]:

import pandas as pd

In [4]:

friend_list = [
    {'age': 25, 'job': 'student'},
    {'age': 25, 'job': 'developer'},
    {'age': 30, 'job': 'teacher'},
]
df = pd.DataFrame(friend_list, index=['John', 'Jenny', 'Nate'], columns = ['age','job'])
df

Out[4]:

	age	job
John	25	student
Jenny	25	developer
Nate	30	teacher

In [5]:

#index 삭제 시
df.drop(['John', 'Nate'])

Out[5]:

	age	job
Jenny	25	developer

In [6]:

#index 삭제 후 저장 시
df = df.drop(['John', 'Nate'])

In [7]:

df

Out[7]:

	age	job
Jenny	25	developer

In [8]:

#복원
friend_list = [
    {'age': 25, 'job': 'student'},
    {'age': 25, 'job': 'developer'},
    {'age': 30, 'job': 'teacher'},
]
df = pd.DataFrame(friend_list, index=['John', 'Jenny', 'Nate'], columns = ['age','job'])
df

Out[8]:

	age	job
John	25	student
Jenny	25	developer
Nate	30	teacher

In [9]:

#index 삭제 후 저장 시 2
df.drop(['John', 'Nate'], inplace = True)

In [10]:

df

Out[10]:

	age	job
Jenny	25	developer

In [13]:

#데이터 수정
friend_list = [
    {'name':'John','age': 25, 'job': 'student'},
    {'name':'Jenny','age': 25, 'job': 'developer'},
    {'name':'Nate','age': 30, 'job': 'teacher'},
]
df = pd.DataFrame(friend_list, columns = ['name','age','job'])
df

Out[13]:

	name	age	job
0	John	25	student
1	Jenny	25	developer
2	Nate	30	teacher

In [15]:

df = df.drop(df.index[[0,2]])

In [16]:

df

Out[16]:

	name	age	job
1	Jenny	25	developer

In [17]:

#데이터 복원
friend_list = [
    {'name':'John','age': 25, 'job': 'student'},
    {'name':'Jenny','age': 25, 'job': 'developer'},
    {'name':'Nate','age': 30, 'job': 'teacher'},
]
df = pd.DataFrame(friend_list, columns = ['name','age','job'])
df

Out[17]:

	name	age	job
0	John	25	student
1	Jenny	25	developer
2	Nate	30	teacher

In [18]:

# 컬럼값에 따라 행 삭제
df = df[df.age>25]

In [19]:

df

Out[19]:

	name	age	job
2	Nate	30	teacher

In [20]:

#데이터 복원
friend_list = [
    {'name':'John','age': 25, 'job': 'student'},
    {'name':'Jenny','age': 25, 'job': 'developer'},
    {'name':'Nate','age': 30, 'job': 'teacher'},
]
df = pd.DataFrame(friend_list, columns = ['name','age','job'])
df

Out[20]:

	name	age	job
0	John	25	student
1	Jenny	25	developer
2	Nate	30	teacher

In [21]:

# 컬럼중에 age 삭제 (열) 두가지 방법
df = df.drop('age', axis = 1)
df.drop('age', axis = 1, inplace = True)

In [22]:

df

Out[22]:

	name	job
0	John	student
1	Jenny	developer
2	Nate	teacher

In [ ]: