import pandas as pd
obj = pd.Series([4, 7, -5, 3])
print(obj)
0 4
1 7
2 -5
3 3
dtype: int64
obj.index
RangeIndex(start=0, stop=4, step=1)
obj.values
array([ 4, 7, -5, 3], dtype=int64)
obj2 = pd.Series([4, 7, -5, 3], index=(['d', 'b', 'a', 'c']))
obj2
d 4
b 7
a -5
c 3
dtype: int64
obj2.index
Index(['d', 'b', 'a', 'c'], dtype='object')
obj2['a']
-5
obj2['d'] = 6
obj2[['c', 'a', 'd']]
c 3
a -5
d 6
dtype: int64
obj2
d 6
b 6
a -5
c 3
dtype: int64
obj2[obj2 > 0]
d 6
b 6
c 3
dtype: int64
obj2*2
d 12
b 12
a -10
c 6
dtype: int64
import numpy as np
np.exp(obj2)
d 403.428793
b 403.428793
a 0.006738
c 20.085537
dtype: float64
'b' in obj2
True
'e' in obj2
False
sdata = {'Ohio': 35000, 'Texas': 71000, 'Oregon': 16000, 'Utah': 5000}
obj3 = pd.Series(sdata)
obj3
Ohio 35000
Oregon 16000
Texas 71000
Utah 5000
dtype: int64
states = ['California', 'Ohio', 'Oregon', 'Texas']
obj4 = pd.Series(sdata, index=states)
obj4
California NaN
Ohio 35000.0
Oregon 16000.0
Texas 71000.0
dtype: float64
pd.isnull(obj4)
California True
Ohio False
Oregon False
Texas False
dtype: bool
pd.notnull(obj4)
California False
Ohio True
Oregon True
Texas True
dtype: bool
obj3
Ohio 35000
Oregon 16000
Texas 71000
Utah 5000
dtype: int64
obj4
California NaN
Ohio 35000.0
Oregon 16000.0
Texas 71000.0
dtype: float64
obj3+obj4
California NaN
Ohio 70000.0
Oregon 32000.0
Texas 142000.0
Utah NaN
dtype: float64
obj4.name = 'population'
obj4.index.name = 'state'
obj4
state
California NaN
Ohio 35000.0
Oregon 16000.0
Texas 71000.0
Name: population, dtype: float64
obj
0 4
1 7
2 -5
3 3
dtype: int64
obj.index = ['zhejiang', 'ningbo', 'caicai', 'nbu']
obj
zhejiang 4
ningbo 7
caicai -5
nbu 3
dtype: int64