pandasは、ある列に基づいてソートする(sort_values)
10341 ワード
: https://pandas.pydata.org/pandas-docs/stable/generated/pandas.DataFrame.sort_values.html
df.sort_values(by="XXXX" , ascending=False) by ascending
#coding=utf-8
import pandas as pd
import numpy as np
# 。
series=pd.Series([3,4,1,6],index=['b','a','d','c'])
frame=pd.DataFrame([[2,4,1,5],[3,1,4,5],[5,1,4,2]],columns=['b','a','d','c'],index=['one','two','three'])
print frame
print series
print 'series :'
print series.sort_index()
print 'series :'
print series.sort_values()
print 'dataframe ( , ascending ):'
print frame.sort_index(ascending=False)
print 'dataframe :'
print frame.sort_index(axis=1)
print 'dataframe :'
print frame.sort_values(by='a')
print ' :'
print frame.sort_values(by=['a','c'])
:
b a d c
one 2 4 1 5
two 3 1 4 5
three 5 1 4 2
b 3
a 4
d 1
c 6
dtype: int64
series :
a 4
b 3
c 6
d 1
dtype: int64
series :
d 1
b 3
a 4
c 6
dtype: int64
dataframe ( , ascending ):
b a d c
two 3 1 4 5
three 5 1 4 2
one 2 4 1 5
dataframe :
a b c d
dd = frame.sort_values(by='b')
Out[38]:
b a d c
one 2 4 1 5
two 3 1 4 5
three 5 1 4 2
dataframe :
b a d c
two 3 1 4 5
three 5 1 4 2
one 2 4 1 5
:
b a d c
three 5 1 4 2
two 3 1 4 5
one 2 4 1 5