基礎操作技能 3之python跨檔案呼叫

#讀取檔案

import pandas as pd 
data = pd.
read_csv
("/data1/data2/data3/data/data.csv"
)#應用os路徑拼接os.path.
join
()函式
#函式的作用連線兩個或者更多的路徑元件
import os
data_path =
'path1'
path2 =
'develop'
path3 =
'data_list'
path = os.path.
join
(data_path, path2, path3)
#在應用的時候直接就可以應用path

#字串

num_str =
'12345678'
sorted
(num_str)
out:
['1'
,'2'
,'3'
,'4'
,'5'
,'6'
,'7'
,'8'
]#列表
num_vec =[1
,3,9
,5,3
]sorted
(num_vec)
out:[1
,3,3
,5,9
]#字典
(預設)
num_dic =
sorted
(num_dic) 
out:[1
,2,3
]#對字典的鍵
sorted
(num_dic.
keys()
) out:[1
,2,3
]#對字典的值
sorted
(num_dic.
values()
) out:
['c'
,'g'
,'q'
]#對鍵值對組成的元組的列表
sorted
(num_dic.
items()
) out:[(
1,'q'),(
2,'g'),(
3,'c')
]#自定義key
#以中間數字為key排序
str_vec =
['a_1.csv'
,'c_5.csv'
,'e_10.csv'
,'p_3.csv'
,'h_7.csv'
]sported
(str_vec, key = lambda d:
int(d.
split
('_')[
-1].
split
('.')[
0]))
out:
['a_1.csv'
,'p_3.csv'
,'c_5.csv'
,'h_7.csv'
,'e_10.csv'
]#加入reverse
sorted
(str_vec, key = lambda d:
int(d.
split
('_')[
-1].
split
('.')[
0]),
reverse=true)
out:
['e_10.csv'
,'h_7.csv'
,'c_5.csv'
,'p_3.csv'
,'a_1.csv'
]#先按照乙個排序，再按照乙個排序
x1 = lambda x:
len(x)#以長度為key
x2 = lambda x: x.
split
('_')[
-1].
split
('.')[
0]x3 = lambda x: x.
split
('_')[
0]#以首字母為key
x4 = lambda x:
(x[0
], x[1]
)#先以x[0]
,後以x[
1]排序

stat lightgbm.py

out: 
file: 『lightgbm.py』
size:
23911 blocks:
48io block:
4096 regular file
device:
811h/
2065d inode:
2406583579 links:
1access:
(0775
/-rwxrwxr-x) uid:
(1010
(1011
access:
2019-11
-2007:
21:28.046885416
-0500
modify:
2019-11
-2007:
21:28.046885416
-0500
change:
2019-11
-2007:
21:28.047885419
-0500

du -a

date

out: mon nov 2519:
16:47est
2019

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