Python (List)

Python - 01

Python6

Python

list1 = ['physics', 'chemistry', 1997, 2000] list2 = [1, 2, 3, 4, 5 ] list3 = ["a", "b", "c", "d"]

(Python 2.0+)

#!/usr/bin/python list1 = ['physics', 'chemistry', 1997, 2000] list2 = [1, 2, 3, 4, 5, 6, 7 ] print "list1[0]: ", list1[0] print "list2[1:5]: ", list2[1:5]

list1[0]:  physics
list2[1:5]:  [2, 3, 4, 5]

append()

(Python 2.0+)

#!/usr/bin/python # -*- coding: UTF-8 -*- list = [] ## list.append('Google') ## append() list.append('Runoob') print list

append()

['Google', 'Runoob']

del

(Python 2.0+)

#!/usr/bin/python list1 = ['physics', 'chemistry', 1997, 2000] print list1 del list1[2] print "After deleting value at index 2 : " print list1

['physics', 'chemistry', 1997, 2000]
After deleting value at index 2 :
['physics', 'chemistry', 2000]

remove()

Python

+ * + *

Python
len([1, 2, 3])	3
[1, 2, 3] + [4, 5, 6]	[1, 2, 3, 4, 5, 6]
['Hi!'] * 4	['Hi!', 'Hi!', 'Hi!', 'Hi!']
3 in [1, 2, 3]	True
for x in [1, 2, 3]: print x,	1 2 3

Python

>>>L = ['Google', 'Runoob', 'Taobao'] >>> L[2] 'Taobao' >>> L[-2] 'Runoob' >>> L[1:] ['Runoob', 'Taobao'] >>>

Python
L[2]	'Taobao'
L[-2]	'Runoob'
L[1:]	['Runoob', 'Taobao']

Python&

Python:


1	cmp(list1, list2)
2	len(list)
3	max(list)
4	min(list)
5	list(seq)

Python:


1	list.append(obj)
2	list.count(obj)
3	list.extend(seq)
4	list.index(obj)
5	list.insert(index, obj)
6	list.pop([index=-1])
7	list.remove(obj)
8	list.reverse()
9	list.sort(cmp=None, key=None, reverse=False)

>>> list_2d = [ [0 for i in range(5)] for i in range(5)] >>> list_2d[0].append(3) >>> list_2d[0].append(5) >>> list_2d[2].append(7) >>> list_2d [[0, 0, 0, 0, 0, 3, 5], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 7], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0]]

#!/usr/bin/python # -*- coding: UTF-8 -*- list01 = ['runoob', 786, 2.23, 'john', 70.2] list02 = [123, 'john'] print list01 print list02 # print list01[0] print list01[-1] print list01[0:3] # print list01 * 2 # print list01 + list02 # print len(list01) # del list02[0] print list02 # print 'john' in list02 # True # for i in list01: print i # print cmp(list01, list02) # / print max([0, 1, 2, 3, 4]) print min([0, 1]) # aTuple = (1,2,3,4) list03 = list(aTuple) print list03 # list03.append(5) print list03 # list03.extend(list01) print list03 # print list03.count(1) # print list03.index('john') # list03.insert(0, 'hello') print list03 # print list03.pop(0) print list03 # list03.remove(1) print list03 # list03.reverse() print list03 # list03.sort() print list03

#encoding=utf-8 import json list_words = [ '', '', '' ] print( list_words ) # print( str(list_words).decode( 'string_escape' ) ) # list_words_result = json.dumps( list_words, encoding='UTF-8', ensure_ascii=False ) print( list_words_result )

# -*- coding: UTF-8 -*- s = 'abcdefg' # 2 print(s[:3]) # 'abc' # print(s[3:]) # 'defg' # print(s[::-1]) # 'gfedcba' # print(s[::2]) # 'aceg' print(range(10)[::2]) # [0, 2, 4, 6, 8] # # 6 2 print(s[6:2:-2]) # 'ge'

243

python cols rows

list_2d = [[0 for col in range(cols)] for row in range(rows)]

tianqixin10 (2017-02-25)

138

python list10 (2017-03-29)

>>> list4=[123,["das","aaa"],234]
>>> list4
>>> "aaa" in list4                  #in
False
>>> "aaa" in list4[1]           #
True
>>> list4[1][1]
'aaa'

9 (2017-12-15)

num_list = [[1,2,3],[4,5,6]]
for i in num_list:
    for j in i:
        print(j)

9 (2018-03-13)

[:-1] :

# -*- coding: UTF-8 -*-

list1 = [1,2,3,4,5,]

print list1

# 
print list1[:-1]

[1, 2, 3, 4, 5]
[1, 2, 3, 4]

a a[:]

id()

a = [1, 2, 3]
id(a)
id(a[:])

a is a[:]

False

a[:] a a[:] a a a append()

8 (2018-05-24)

['\xe4\xbd\xa0', '\xe6\x88\x91', '\xe4\xbb\x96']
['', '', '']
["", "", ""]

8 (2018-07-24)

remove del

>>> a=[1,2,3,5,4,2,6]
>>> a.remove(a[5])
>>> a
[1, 3, 5, 4, 2, 6]

remove

>>> a=[1,2,3,5,4,2,6]
>>> del(a[5])
>>> a
[1, 2, 3, 5, 4, 6]

del 0

8 (2018-08-08)

test = ['a','','b','','c','','']
test = [i for i in test if i != '']

print(test)

['a', 'b', 'c']

Lanyue8 (2018-10-18)

Paris8 (2018-10-24)

a = [0,2,3,4,5,6,7,8,22,44,55]

# 2 10 3  3 
b = a[2:10:3]
print(b)

[3, 6, 22]

jia7 (2019-04-19)

List Comprehensions

[expression for iter_val in iterable if cond_expr]

[expression]
[for iter_val in iterable]
[if cond_expr]for

for

>>> print[(x,y)for x in [1,2]for y in [3,4]]
[(1, 3), (1, 4), (2, 3), (2, 4)]
>>> print[(x,y)for x in [1,2]for y in [3,x]]
[(1, 3), (1, 1), (2, 3), (2, 2)]
>>>

>>> print[(x,y)for x in [1,y]for y in [3,4]]
[(1, 3), (1, 4), (2, 3), (2, 4)]
>>>

7 (2019-05-06)

--

Python

Python (List)

(Python 2.0+)

(Python 2.0+)

(Python 2.0+)

Python

Python

Python&

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