ipython的使用
地址：https://ipython.org/install.html
简单的安装方法：pip install ipython
一些方便的使用方法：
- 输入要查看的对象，然后输入一个问号可以查看API，输入两个问号可以查看代码
- 可以直接调用shell命令，在前面带上！即可
- 按Tab可以自动语法补全
- 最近的命令输出结果，可以从_、__、___三个变量获得
- %hist或者%history查看历史命令
- %timeit可以进行命令的执行时间测试
数据结构与算法
列表生成器
In [5]: a=[1,2,3] In [6]: [x*x for x in a if x>1] Out[6]: [4, 9]
|
1
2
3
4
|
In
[
5
]
:
a
=
[
1
,
2
,
3
]
In
[
6
]
:
[
x*
x
for
x
in
a
if
x
>
1
]
Out
[
6
]
:
[
4
,
9
]
|
集合生成器（和列表生成器相同）
In [7]: a=[1,2,3] In [8]: s = {x*x for x in a if x>1} In [9]: s Out[9]: {4, 9} In [10]: type(s) Out[10]: set
|
1
2
3
4
5
6
7
8
9
|
In
[
7
]
:
a
=
[
1
,
2
,
3
]
In
[
8
]
:
s
=
{
x*
x
for
x
in
a
if
x
>
1
}
In
[
9
]
:
s
Out
[
9
]
:
{
4
,
9
}
In
[
10
]
:
type
(
s
)
Out
[
10
]
:
set
|
字典生成器
In [11]: a=[1,2,3] In [12]: {str(x):x+1 for x in a if x>1} Out[12]: {'2': 3, '3': 4}
|
1
2
3
4
|
In
[
11
]
:
a
=
[
1
,
2
,
3
]
In
[
12
]
:
{
str
(
x
)
:
x
+
1
for
x
in
a
if
x
>
1
}
Out
[
12
]
:
{
'2'
:
3
,
'3'
:
4
}
|
range和xrange的使用
In [13]: range? Docstring: range(stop) -> list of integers range(start, stop[, step]) -> list of integers In [14]: range(10) Out[14]: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] In [15]: range(3,10) Out[15]: [3, 4, 5, 6, 7, 8, 9] In [16]: xrange? Docstring: xrange(stop) -> xrange object xrange(start, stop[, step]) -> xrange object In [19]: list(xrange(3,10)) Out[19]: [3, 4, 5, 6, 7, 8, 9] In [21]: list(xrange(10)) Out[21]: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
|
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18
19
20
21
22
|
In
[
13
]
:
range
?
Docstring
:
range
(
stop
)
->
list
of
integers
range
(
start
,
stop
[
,
step
]
)
->
list
of
integers
In
[
14
]
:
range
(
10
)
Out
[
14
]
:
[
0
,
1
,
2
,
3
,
4
,
5
,
6
,
7
,
8
,
9
]
In
[
15
]
:
range
(
3
,
10
)
Out
[
15
]
:
[
3
,
4
,
5
,
6
,
7
,
8
,
9
]
In
[
16
]
:
xrange
?
Docstring
:
xrange
(
stop
)
->
xrange
object
xrange
(
start
,
stop
[
,
step
]
)
->
xrange
object
In
[
19
]
:
list
(
xrange
(
3
,
10
)
)
Out
[
19
]
:
[
3
,
4
,
5
,
6
,
7
,
8
,
9
]
In
[
21
]
:
list
(
xrange
(
10
)
)
Out
[
21
]
:
[
0
,
1
,
2
,
3
,
4
,
5
,
6
,
7
,
8
,
9
]
|
range和xrange的用法相同，只是range会直接生成一个内存列表，xrange会生成一个生产器，xrange的效率更高，更节省内存
filter用于过滤数据
In [22]: filter? Docstring: filter(function or None, sequence) -> list, tuple, or string Return those items of sequence for which function(item) is true. If function is None, return the items that are true. If sequence is a tuple or string, return the same type, else return a list. Type: builtin_function_or_method In [23]: filter(lambda x:x%3==0, xrange(10)) Out[23]: [0, 3, 6, 9]
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7
8
9
10
11
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In
[
22
]
:
filter
?
Docstring
:
filter
(
function
or
None
,
sequence
)
->
list
,
tuple
,
or
string
Return
those
items
of
sequence
for
which
function
(
item
)
is
true
.
If
function
is
None
,
return
the
items
that
are
true
.
If
sequence
is
a
tuple
or
string
,
return
the
same
type
,
else
return
a
list
.
Type
:
builtin_function_or_method
In
[
23
]
:
filter
(
lambda
x
:
x
%
3
==
0
,
xrange
(
10
)
)
Out
[
23
]
:
[
0
,
3
,
6
,
9
]
|
使用collections.namedtuple给列表或者元组命名
In [24]: from collections import namedtuple In [30]: Point = namedtuple('Point', ['x', 'y']) In [31]: p = Point(11, 22) In [32]: p.__dict__ Out[32]: OrderedDict([('x', 11), ('y', 22)]) In [33]: p.x Out[33]: 11 In [34]: p.y Out[34]: 22
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13
14
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In
[
24
]
:
from
collections
import
namedtuple
In
[
30
]
:
Point
=
namedtuple
(
'Point'
,
[
'x'
,
'y'
]
)
In
[
31
]
:
p
=
Point
(
11
,
22
)
In
[
32
]
:
p
.
__dict__
Out
[
32
]
:
OrderedDict
(
[
(
'x'
,
11
)
,
(
'y'
,
22
)
]
)
In
[
33
]
:
p
.
x
Out
[
33
]
:
11
In
[
34
]
:
p
.
y
Out
[
34
]
:
22
|
random的使用
In [35]: from random import randint In [36]: randint? Signature: randint(a, b) Docstring: Return random integer in range [a, b], including both end points. File: /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/random.py Type: instancemethod In [37]: randint(1,10) Out[37]: 2
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9
10
11
12
|
In
[
35
]
:
from
random
import
randint
In
[
36
]
:
randint
?
Signature
:
randint
(
a
,
b
)
Docstring
:
Return
random
integer
in
range
[
a
,
b
]
,
including
both
end
points
.
File
:
/
Library
/
Frameworks
/
Python
.
framework
/
Versions
/
2.7
/
lib
/
python2
.
7
/
random
.
py
Type
:
instancemethod
In
[
37
]
:
randint
(
1
,
10
)
Out
[
37
]
:
2
|
统计序列元素的频度和TOP N
In [42]: from collections import Counter In [43]: Counter? In [44]: c = Counter('aaabbbbccccccddddddeeeeee') In [45]: c Out[45]: Counter({'a': 3, 'b': 4, 'c': 6, 'd': 6, 'e': 6}) In [46]: c.most_common(3) Out[46]: [('c', 6), ('e', 6), ('d', 6)]
|
1
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3
4
5
6
7
8
9
10
11
|
In
[
42
]
:
from
collections
import
Counter
In
[
43
]
:
Counter
?
In
[
44
]
:
c
=
Counter
(
'aaabbbbccccccddddddeeeeee'
)
In
[
45
]
:
c
Out
[
45
]
:
Counter
(
{
'a'
:
3
,
'b'
:
4
,
'c'
:
6
,
'd'
:
6
,
'e'
:
6
}
)
In
[
46
]
:
c
.
most_common
(
3
)
Out
[
46
]
:
[
(
'c'
,
6
)
,
(
'e'
,
6
)
,
(
'd'
,
6
)
]
|
将字典按value排序
In [47]: from random import randint In [48]: keys = 'abcdefg' In [50]: d = {x:randint(90,100) for x in keys} In [51]: d Out[51]: {'a': 90, 'b': 100, 'c': 94, 'd': 97, 'e': 94, 'f': 95, 'g': 91} In [53]: d.items() Out[53]: [('a', 90), ('c', 94), ('b', 100), ('e', 94), ('d', 97), ('g', 91), ('f', 95)] In [54]: sorted? Docstring: sorted(iterable, cmp=None, key=None, reverse=False) --> new sorted list Type: builtin_function_or_method In [55]: sorted(d.items(), key=lambda x : x[1]) Out[55]: [('a', 90), ('g', 91), ('c', 94), ('e', 94), ('f', 95), ('d', 97), ('b', 100)]
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3
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5
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7
8
9
10
11
12
13
14
15
16
17
18
|
In
[
47
]
:
from
random
import
randint
In
[
48
]
:
keys
=
'abcdefg'
In
[
50
]
:
d
=
{
x
:
randint
(
90
,
100
)
for
x
in
keys
}
In
[
51
]
:
d
Out
[
51
]
:
{
'a'
:
90
,
'b'
:
100
,
'c'
:
94
,
'd'
:
97
,
'e'
:
94
,
'f'
:
95
,
'g'
:
91
}
In
[
53
]
:
d
.
items
(
)
Out
[
53
]
:
[
(
'a'
,
90
)
,
(
'c'
,
94
)
,
(
'b'
,
100
)
,
(
'e'
,
94
)
,
(
'd'
,
97
)
,
(
'g'
,
91
)
,
(
'f'
,
95
)
]
In
[
54
]
:
sorted
?
Docstring
:
sorted
(
iterable
,
cmp
=
None
,
key
=
None
,
reverse
=
False
)
--
>
new
sorted
list
Type
:
builtin_function_or_method
In
[
55
]
:
sorted
(
d
.
items
(
)
,
key
=
lambda
x
:
x
[
1
]
)
Out
[
55
]
:
[
(
'a'
,
90
)
,
(
'g'
,
91
)
,
(
'c'
,
94
)
,
(
'e'
,
94
)
,
(
'f'
,
95
)
,
(
'd'
,
97
)
,
(
'b'
,
100
)
]
|
获得多个词典的key的交集
In [99]: from random import randint, sample In [100]: dd1 = {x:randint(90,100) for x in sample('abcdefghij', 5)} In [101]: dd2 = {x:randint(90,100) for x in sample('abcdefghij', 5)} In [102]: dd3 = {x:randint(90,100) for x in sample('abcdefghij', 5)} In [103]: dd1 Out[103]: {'b': 100, 'c': 97, 'd': 100, 'e': 97, 'f': 92} In [104]: dd2 Out[104]: {'a': 100, 'c': 90, 'g': 93, 'h': 93, 'j': 90} In [105]: dd3 Out[105]: {'c': 96, 'e': 93, 'f': 91, 'h': 97, 'j': 90} In [106]: mp = map(dict.viewkeys, (dd1, dd2, dd3)) In [107]: mp Out[107]: [dict_keys(['c', 'b', 'e', 'd', 'f']), dict_keys(['a', 'h', 'c', 'j', 'g']), dict_keys(['h', 'c', 'j', 'e', 'f'])] In [108]: reduce(lambda x,y: x&y, mp) Out[108]: {'c'}
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5
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7
8
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12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
|
In
[
99
]
:
from
random
import
randint
,
sample
In
[
100
]
:
dd1
=
{
x
:
randint
(
90
,
100
)
for
x
in
sample
(
'abcdefghij'
,
5
)
}
In
[
101
]
:
dd2
=
{
x
:
randint
(
90
,
100
)
for
x
in
sample
(
'abcdefghij'
,
5
)
}
In
[
102
]
:
dd3
=
{
x
:
randint
(
90
,
100
)
for
x
in
sample
(
'abcdefghij'
,
5
)
}
In
[
103
]
:
dd1
Out
[
103
]
:
{
'b'
:
100
,
'c'
:
97
,
'd'
:
100
,
'e'
:
97
,
'f'
:
92
}
In
[
104
]
:
dd2
Out
[
104
]
:
{
'a'
:
100
,
'c'
:
90
,
'g'
:
93
,
'h'
:
93
,
'j'
:
90
}
In
[
105
]
:
dd3
Out
[
105
]
:
{
'c'
:
96
,
'e'
:
93
,
'f'
:
91
,
'h'
:
97
,
'j'
:
90
}
In
[
106
]
:
mp
=
map
(
dict
.
viewkeys
,
(
dd1
,
dd2
,
dd3
)
)
In
[
107
]
:
mp
Out
[
107
]
:
[
dict_keys
(
[
'c'
,
'b'
,
'e'
,
'd'
,
'f'
]
)
,
dict_keys
(
[
'a'
,
'h'
,
'c'
,
'j'
,
'g'
]
)
,
dict_keys
(
[
'h'
,
'c'
,
'j'
,
'e'
,
'f'
]
)
]
In
[
108
]
:
reduce
(
lambda
x
,
y
:
x
&
y
,
mp
)
Out
[
108
]
:
{
'c'
}
|
怎样让字典按照插入有序
In [122]: from collections import OrderedDict In [123]: d = OrderedDict() In [124]: d['x'] = 1 In [125]: d['y'] = 2 In [126]: d['a'] = 2 In [127]: d['b'] = 2 In [128]: d Out[128]: OrderedDict([('x', 1), ('y', 2), ('a', 2), ('b', 2)])
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
|
In
[
122
]
:
from
collections
import
OrderedDict
In
[
123
]
:
d
=
OrderedDict
(
)
In
[
124
]
:
d
[
'x'
]
=
1
In
[
125
]
:
d
[
'y'
]
=
2
In
[
126
]
:
d
[
'a'
]
=
2
In
[
127
]
:
d
[
'b'
]
=
2
In
[
128
]
:
d
Out
[
128
]
:
OrderedDict
(
[
(
'x'
,
1
)
,
(
'y'
,
2
)
,
(
'a'
,
2
)
,
(
'b'
,
2
)
]
)
|
怎样实现长度为N的队列功能
In [138]: from collections import deque In [139]: deque? Docstring: deque([iterable[, maxlen]]) --> deque object Build an ordered collection with optimized access from its endpoints. File: /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/collections.py Type: type In [141]: d = deque([], 3) In [142]: d.append(1) In [143]: d.append(2) In [144]: d.append(3) In [145]: d.append(4) In [146]: d Out[146]: deque([2, 3, 4])
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
|
In
[
138
]
:
from
collections
import
deque
In
[
139
]
:
deque
?
Docstring
:
deque
(
[
iterable
[
,
maxlen
]
]
)
--
>
deque
object
Build
an
ordered
collection
with
optimized
access
from
its
endpoints
.
File
:
/
Library
/
Frameworks
/
Python
.
framework
/
Versions
/
2.7
/
lib
/
python2
.
7
/
collections
.
py
Type
:
type
In
[
141
]
:
d
=
deque
(
[
]
,
3
)
In
[
142
]
:
d
.
append
(
1
)
In
[
143
]
:
d
.
append
(
2
)
In
[
144
]
:
d
.
append
(
3
)
In
[
145
]
:
d
.
append
(
4
)
In
[
146
]
:
d
Out
[
146
]
:
deque
(
[
2
,
3
,
4
]
)
|
迭代器
怎样齐头并进并行的遍历多个集合
In [147]: names = [x for x in 'abcdefg'] In [148]: ages = [x for x in range(21, 28)] In [149]: scores = [randint(90,100) for x in range(7)] In [150]: names Out[150]: ['a', 'b', 'c', 'd', 'e', 'f', 'g'] In [151]: ages Out[151]: [21, 22, 23, 24, 25, 26, 27] In [152]: scores Out[152]: [93, 90, 95, 97, 91, 93, 92] In [153]: In [153]: zip? Docstring: zip(seq1 [, seq2 [...]]) -> [(seq1[0], seq2[0] ...), (...)] Return a list of tuples, where each tuple contains the i-th element from each of the argument sequences. The returned list is truncated in length to the length of the shortest argument sequence. Type: builtin_function_or_method In [154]: for name,age,score in zip(names, ages, scores): ...: print name,age,score ...: a 21 93 b 22 90 c 23 95 d 24 97 e 25 91 f 26 93 g 27 92
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
|
In
[
147
]
:
names
=
[
x
for
x
in
'abcdefg'
]
In
[
148
]
:
ages
=
[
x
for
x
in
range
(
21
,
28
)
]
In
[
149
]
:
scores
=
[
randint
(
90
,
100
)
for
x
in
range
(
7
)
]
In
[
150
]
:
names
Out
[
150
]
:
[
'a'
,
'b'
,
'c'
,
'd'
,
'e'
,
'f'
,
'g'
]
In
[
151
]
:
ages
Out
[
151
]
:
[
21
,
22
,
23
,
24
,
25
,
26
,
27
]
In
[
152
]
:
scores
Out
[
152
]
:
[
93
,
90
,
95
,
97
,
91
,
93
,
92
]
In
[
153
]
:
In
[
153
]
:
zip
?
Docstring
:
zip
(
seq1
[
,
seq2
[
.
.
.
]
]
)
->
[
(
seq1
[
0
]
,
seq2
[
0
]
.
.
.
)
,
(
.
.
.
)
]
Return
a
list
of
tuples
,
where
each
tuple
contains
the
i
-
th
element
from
each
of
the
argument
sequences
.
The
returned
list
is
truncated
in
length
to
the
length
of
the
shortest
argument
sequence
.
Type
:
builtin_function_or_method
In
[
154
]
:
for
name
,
age
,
score
in
zip
(
names
,
ages
,
scores
)
:
.
.
.
:
print
name
,
age
,
score
.
.
.
:
a
21
93
b
22
90
c
23
95
d
24
97
e
25
91
f
26
93
g
27
92
|
怎样串行的遍历多个集合
In [158]: lista = (randint(60,70) for x in range(10)) In [159]: list(lista) Out[159]: [65, 60, 62, 64, 63, 60, 68, 67, 61, 62] In [160]: listb = [randint(90,100) for x in range(20)] In [161]: listb Out[161]: [98, 96, 97, 98, 95, 95, 90, 99, 92, 92, 99, 92, 100, 95, 100, 100, 93, 91, 92, 98] In [163]: from itertools import chain In [164]: chain? Docstring: chain(*iterables) --> chain object Return a chain object whose .next() method returns elements from the first iterable until it is exhausted, then elements from the next iterable, until all of the iterables are exhausted. File: /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/itertools.so Type: type In [165]: for x in chain(lista, listb): ...: print x, ...: 98 96 97 98 95 95 90 99 92 92 99 92 100 95 100 100 93 91 92 98
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
|
In
[
158
]
:
lista
=
(
randint
(
60
,
70
)
for
x
in
range
(
10
)
)
In
[
159
]
:
list
(
lista
)
Out
[
159
]
:
[
65
,
60
,
62
,
64
,
63
,
60
,
68
,
67
,
61
,
62
]
In
[
160
]
:
listb
=
[
randint
(
90
,
100
)
for
x
in
range
(
20
)
]
In
[
161
]
:
listb
Out
[
161
]
:
[
98
,
96
,
97
,
98
,
95
,
95
,
90
,
99
,
92
,
92
,
99
,
92
,
100
,
95
,
100
,
100
,
93
,
91
,
92
,
98
]
In
[
163
]
:
from
itertools
import
chain
In
[
164
]
:
chain
?
Docstring
:
chain
(
*
iterables
)
--
>
chain
object
Return
a
chain
object
whose
.
next
(
)
method
returns
elements
from
the
first
iterable
until
it
is
exhausted
,
then
elements
from
the
next
iterable
,
until
all
of
the
iterables
are
exhausted
.
File
:
/
Library
/
Frameworks
/
Python
.
framework
/
Versions
/
2.7
/
lib
/
python2
.
7
/
lib
-
dynload
/
itertools
.
so
Type
:
type
In
[
165
]
:
for
x
in
chain
(
lista
,
listb
)
:
.
.
.
:
print
x
,
.
.
.
:
98
96
97
98
95
95
90
99
92
92
99
92
100
95
100
100
93
91
92
98
|
字符串
使用多种分隔符拆分字符串
In [166]: s = 'a,b;c/d' In [167]: import re In [169]: re.sub? Signature: re.sub(pattern, repl, string, count=0, flags=0) Docstring: Return the string obtained by replacing the leftmost non-overlapping occurrences of the pattern in string by the replacement repl. repl can be either a string or a callable; if a string, backslash escapes in it are processed. If it is a callable, it's passed the match object and must return a replacement string to be used. File: /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/re.py Type: function In [171]: re.sub(r'[,;/]', '-', s) Out[171]: 'a-b-c-d'
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
|
In
[
166
]
:
s
=
'a,b;c/d'
In
[
167
]
:
import
re
In
[
169
]
:
re
.
sub
?
Signature
:
re
.
sub
(
pattern
,
repl
,
string
,
count
=
0
,
flags
=
0
)
Docstring
:
Return
the
string
obtained
by
replacing
the
leftmost
non
-
overlapping
occurrences
of
the
pattern
in
string
by
the
replacement
repl
.
repl
can
be
either
a
string
or
a
callable
;
if
a
string
,
backslash
escapes
in
it
are
processed
.
If
it
is
a
callable
,
it
's passed the match object and must return
a replacement string to be used.
File: /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/re.py
Type: function
In [171]: re.sub(r'
[
,
;
/
]
', '
-
', s)
Out[171]: '
a
-
b
-
c
-
d'
|
如果进行字符串的模糊搜索与部分替换
In [172]: s = 'things happend in 2017-08-09, it is a sunddy' In [175]: re.sub(r'(\d{4})-(\d{2})-(\d{2})', r'\2-\1-\3', s) Out[175]: 'things happend in 08-2017-09, it is a sunddy'
|
1
2
3
4
|
In
[
172
]
:
s
=
'things happend in 2017-08-09, it is a sunddy'
In
[
175
]
:
re
.
sub
(
r
'(\d{4})-(\d{2})-(\d{2})'
,
r
'\2-\1-\3'
,
s
)
Out
[
175
]
:
'things happend in 08-2017-09, it is a sunddy'
|
列表JOIN时如果有数字元素怎么办
In [176]: print '\t'.join([str(x) for x in ['a','b',33,4.0,'e']]) a b 33 4.0 e
|
1
2
|
In
[
176
]
:
print
'\t'
.
join
(
[
str
(
x
)
for
x
in
[
'a'
,
'b'
,
33
,
4.0
,
'e'
]
]
)
a
b
33
4.0
e
|
文件
如何使用临时文件
In [186]: from tempfile import TemporaryFile,NamedTemporaryFile In [187]: t = TemporaryFile() In [188]: t.write('aa') In [189]: t.close() In [191]: NamedTemporaryFile? Signature: NamedTemporaryFile(mode='w+b', bufsize=-1, suffix='', prefix='tmp', dir=None, delete=True) Docstring: Create and return a temporary file. Arguments: 'prefix', 'suffix', 'dir' -- as for mkstemp. 'mode' -- the mode argument to os.fdopen (default "w+b"). 'bufsize' -- the buffer size argument to os.fdopen (default -1). 'delete' -- whether the file is deleted on close (default True). The file is created as mkstemp() would do it. Returns an object with a file-like interface; the name of the file is accessible as its 'name' attribute. The file will be automatically deleted when it is closed unless the 'delete' argument is set to False. File: /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/tempfile.py Type: function In [192]: t = NamedTemporaryFile() In [193]: t.write("a") In [194]: t.name Out[194]: '/var/folders/sc/rpg0yq054hb7vdr83ms1rp2w0000gn/T/tmpQIONuU'
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
|
In
[
186
]
:
from
tempfile
import
TemporaryFile
,
NamedTemporaryFile
In
[
187
]
:
t
=
TemporaryFile
(
)
In
[
188
]
:
t
.
write
(
'aa'
)
In
[
189
]
:
t
.
close
(
)
In
[
191
]
:
NamedTemporaryFile
?
Signature
:
NamedTemporaryFile
(
mode
=
'w+b'
,
bufsize
=
-
1
,
suffix
=
''
,
prefix
=
'tmp'
,
dir
=
None
,
delete
=
True
)
Docstring
:
Create
and
return
a
temporary
file
.
Arguments
:
'prefix'
,
'suffix'
,
'dir'
--
as
for
mkstemp
.
'mode'
--
the
mode
argument
to
os
.
fdopen
(
default
"w+b"
)
.
'bufsize'
--
the
buffer
size
argument
to
os
.
fdopen
(
default
-
1
)
.
'delete'
--
whether
the
file
is
deleted
on
close
(
default
True
)
.
The
file
is
created
as
mkstemp
(
)
would
do
it
.
Returns
an
object
with
a
file
-
like
interface
;
the
name
of
the
file
is
accessible
as
its
'name'
attribute
.
The
file
will
be
automatically
deleted
when
it
is
closed
unless
the
'delete'
argument
is
set
to
False
.
File
:
/
Library
/
Frameworks
/
Python
.
framework
/
Versions
/
2.7
/
lib
/
python2
.
7
/
tempfile
.
py
Type
:
function
In
[
192
]
:
t
=
NamedTemporaryFile
(
)
In
[
193
]
:
t
.
write
(
"a"
)
In
[
194
]
:
t
.
name
Out
[
194
]
:
'/var/folders/sc/rpg0yq054hb7vdr83ms1rp2w0000gn/T/tmpQIONuU'
|
并发编程
如何使用多线程
In [8]: cat multi_threading.py from threading import Thread def func(x): print x, x*x*x ts = [] for x in range(10): t = Thread(target=func, args=(x,)) t.start() ts.append(t) for t in ts: t.join() print 'main thread over' In [9]: %run multi_threading.py 0 0 1 1 2 8 3 27 4 64 5 125 6 216 7 343 8 512 9 729 main thread over
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
|
In
[
8
]
:
cat
multi_threading
.
py
from
threading
import
Thread
def
func
(
x
)
:
print
x
,
x
*
x
*
x
ts
=
[
]
for
x
in
range
(
10
)
:
t
=
Thread
(
target
=
func
,
args
=
(
x
,
)
)
t
.
start
(
)
ts
.
append
(
t
)
for
t
in
ts
:
t
.
join
(
)
print
'main thread over'
In
[
9
]
:
%
run
multi_threading
.
py
0
0
1
1
2
8
3
27
4
64
5
125
6
216
7
343
8
512
9
729
main
thread
over
|
上一中是直接用函数执行，第二种是先创建一个类继承自Thread类
In [18]: cat multi_threading_class.py from threading import Thread class MyThread(Thread): def __init__(self, x): Thread.__init__(self) self.x = x def run(self): print self.x, self.x*self.x*self.x ts = [] for x in range(10): t = MyThread(x) t.start() ts.append(t) for t in ts: t.join() print 'main thread over' In [19]: %run multi_threading_class.py 0 0 1 1 2 8 3 27 4 64 5 125 6 216 7 343 8 512 9 729 main thread over
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
|
In
[
18
]
:
cat
multi_threading_class
.
py
from
threading
import
Thread
class
MyThread
(
Thread
)
:
def
__init__
(
self
,
x
)
:
Thread
.
__init__
(
self
)
self
.
x
=
x
def
run
(
self
)
:
print
self
.
x
,
self
.
x
*
self
.
x
*
self
.
x
ts
=
[
]
for
x
in
range
(
10
)
:
t
=
MyThread
(
x
)
t
.
start
(
)
ts
.
append
(
t
)
for
t
in
ts
:
t
.
join
(
)
print
'main thread over'
In
[
19
]
:
%
run
multi_threading_class
.
py
0
0
1
1
2
8
3
27
4
64
5
125
6
216
7
343
8
512
9
729
main
thread
over
|
线程间通信-生产者消费者模式
In [8]: cat producer_consumer.py #coding:utf8 from threading import Thread,currentThread from Queue import Queue from time import sleep from random import randint,sample from itertools import chain class Producer(Thread): def __init__(self, queue): Thread.__init__(self) self.queue = queue def run(self): for x in range(5): sleep(randint(1,3)) ele = sample('abcdefg',1)[0] print 'producer %s: %s'%(currentThread().name, ele) self.queue.put(ele) class Consumer(Thread): def __init__(self, queue): Thread.__init__(self) self.setDaemon(True) self.queue = queue def run(self): while(True): e = self.queue.get() sleep(1) print 'consumer %s: %s' % (currentThread().name, e) queue = Queue() tps = [] for x in range(3): tp = Producer(queue) tp.start() tps.append(tp) for x in range(2): tc = Consumer(queue) tc.start() for t in tps: t.join() print 'main thread over' In [9]: %run producer_consumer.py producer Thread-301: a ^Cconsumer Thread-304: a producer Thread-302: c producer Thread-303: g producer Thread-301: c consumer Thread-304: g consumer Thread-305: c producer Thread-303: b
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
|
In
[
8
]
:
cat
producer_consumer
.
py
#coding:utf8
from
threading
import
Thread
,
currentThread
from
Queue
import
Queue
from
time
import
sleep
from
random
import
randint
,
sample
from
itertools
import
chain
class
Producer
(
Thread
)
:
def
__init__
(
self
,
queue
)
:
Thread
.
__init__
(
self
)
self
.
queue
=
queue
def
run
(
self
)
:
for
x
in
range
(
5
)
:
sleep
(
randint
(
1
,
3
)
)
ele
=
sample
(
'abcdefg'
,
1
)
[
0
]
print
'producer %s: %s'
%
(
currentThread
(
)
.
name
,
ele
)
self
.
queue
.
put
(
ele
)
class
Consumer
(
Thread
)
:
def
__init__
(
self
,
queue
)
:
Thread
.
__init__
(
self
)
self
.
setDaemon
(
True
)
self
.
queue
=
queue
def
run
(
self
)
:
while
(
True
)
:
e
=
self
.
queue
.
get
(
)
sleep
(
1
)
print
'consumer %s: %s'
%
(
currentThread
(
)
.
name
,
e
)
queue
=
Queue
(
)
tps
=
[
]
for
x
in
range
(
3
)
:
tp
=
Producer
(
queue
)
tp
.
start
(
)
tps
.
append
(
tp
)
for
x
in
range
(
2
)
:
tc
=
Consumer
(
queue
)
tc
.
start
(
)
for
t
in
tps
:
t
.
join
(
)
print
'main thread over'
In
[
9
]
:
%
run
producer_consumer
.
py
producer
Thread
-
301
:
a
^
Cconsumer
Thread
-
304
:
a
producer
Thread
-
302
:
c
producer
Thread
-
303
:
g
producer
Thread
-
301
:
c
consumer
Thread
-
304
:
g
consumer
Thread
-
305
:
c
producer
Thread
-
303
:
b
|
