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

SAS data步的操作技能點 3

1 日期計算 dataage infile e 11 6 tomdate.dat input 1randdate mmddyy10.12brthdate mmddyy10.23date12 mmddyy10.agedays randdate brthdate ageyrs randdate brth...

Python基礎之檔案操作

python的檔案操作還是比較簡單的基本分為三步 開啟，讀寫，關閉 檔案開啟 f open db r 開啟 f.read 讀 f.close 關閉 為了避免程式設計師忘記最後一步關閉，優雅的python使用了以下語句 with open db r as f,open db2 r as f2 opra...

python基礎之檔案操作

開啟檔案並輸出檔案內容模板 f open flie mode r encoding utf 8 data f.read 返回整個檔案資料 data f.readlines 以列 式，返回整個檔案資料 print data f.close flie檔案路徑 相對路徑或者絕對路徑 mode檔案開啟模式 ...