Python学习系列(五)

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本节主要学习Python 3.1的复杂数据类型，内存管理和模块，下面做了一个Sample:
'''
Created on 2010-4-5
@author: Jamson Huang
'''
import os
#import filecmp
import copy
#Python常用的module: os
#pdb=>调试器
#logging=>记录器
#profile,hotshot,cProfile:性能调试器
#所有类的基类都是Object
if __name__ == '__main__':
#global zone   
tempStr = 'start to learn python class'
intA = 5
intB = 6
#type():the type of all objects is 'type'   
def typeFunc():
print(type('42'))
print(type(type('42')))
print()
typeFunc()
#NoneType/None(Python 3.1)<=>Null(Python 2.6)
def noneFunc():
print(type(None))
if (None):
print('None is False')
else:
print('None is not True')
a = 'adajkd'
#两个对象之间的比较        
if (a is None):
print('a is None')
else:
print('a is not None')
noneFunc()
def moduleFunc():
print(os.name)
moduleFunc()
#CALL self-definiton class
#    policy = Policy()
#    policy.setPolicyId('1111111')
#    print(policy.getPolicyId())   
#Python的内存管理：同java语言，程序员本身不需要关心它。由于python采用引用计数的方式，所以垃圾收集器
#会回收那些计数器为0的变量和类，当然，也可以用del来直接做回收处理。其实，这点同java类似。  
#Seqence[start1:end1,start2:ed2,...]
def seqFunc():
print(tempStr[::-1])
print(tempStr[::-2])
seqFunc()
#内建函数:cmp(obj1,obj2)/str(obj)/repr(obj),'obj'/type()/isinstance()
#    print(cmp(str(intA), str(intB)))
#工厂函数:file()/dict()/bool()/tuple()/basestring()/unicode()
print(str(tempStr))
#id():变量和实例在内存中的标识符
#存储模型：1.标量/原子类型（数值，字符串）2.容器模型（列表，元组，字典）   
#更新模型: 1.变量类型：列表,字典；2.不可变类型：数值，字符串，元组
#访问模型: 1.直接访问：数字； 2.顺序访问:字符串，列表，元组；3.映射访问:字典   
def complexTypeFunc():
print(id(tempStr))   
aList = ['china', 'shanghai']
print(id(aList))
aList.append('Python')
print(aList)
print(id(aList))
#列表/元组类型:列表是可变类型，而元组是不可变类型
aList.append(['3333','4444'])
print(aList)
print(aList[3])
aTuple = ('china','shanghai',['aaaa','bbbb'])
print(aTuple)
print(id(aTuple))
print(aTuple.index('shanghai'))
print(aTuple[::1])
print(aTuple[:1])
print(aTuple[1])
#copy和deepCopy:deepCopy会完全Create一个新的容器类型。        
newTuple = copy.copy(aTuple)
print('Copy:', newTuple)
print(id(newTuple))
newDeepTuple = copy.deepcopy(aTuple)
print('deepCopy:', newDeepTuple)
print(id(newDeepTuple))
complexTypeFunc()     
run Python, Console输出如下：
<class 'str'>
<class 'type'>
<class 'NoneType'>
None is not True
a is not None
nt
ssalc nohtyp nrael ot trats
sacnhy re ttas
start to learn python class
11610784
12877952
['china', 'shanghai', 'Python']
12877952
['china', 'shanghai', 'Python', ['3333', '4444']]
['3333', '4444']
('china', 'shanghai', ['aaaa', 'bbbb'])
12868104
1
('china', 'shanghai', ['aaaa', 'bbbb'])
('china',)
shanghai
Copy: ('china', 'shanghai', ['aaaa', 'bbbb'])
12868104
deepCopy: ('china', 'shanghai', ['aaaa', 'bbbb'])
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