【数据结构实践】手把手带你实现 Python 自定义数组

classClassName：#类名使用大驼峰法，即首字母大写#类的语句块如类的成员属性...
类的方法...

classDog:
def__init__(self, name):
self.name=name# 类的实例化如下d1=Dog("小北")

classMyNArrays:
#过滤非数字类型的元素def___isNumber(self, n):
ifnotisinstance(n,(int,float,complex)):
returnFalsereturnTrue#类属性等初始化def__init__(self,*args):
ifnotargs:
self.__value= []
else:
forarginargs:
ifnotself.___isNumber(arg):
print('All elements must be numbers')
returnself.__value=list(args)
@propertydefgetValue(self):
returnself.__value#析构函数，释放内部封装的列表def__del__(self):
delself.__value#重载运算符+def__add__(self, other):
#数组中每个元素都与数字other相加，或者两个数组相加，会得到一个新数组ifself.___isNumber(other):
#数组与数字other相加b=MyNArrays()
b.__value= [item+otherforiteminself.__value]
returnbelifisinstance(other,MyNArrays):
#两个数组对应元素相加if (len(other.__value) ==len(self.__value)):
c=MyNArrays()
c.__value= [i+jfori,jinzip(self.__value,other.__value)]
returncelse:
print('Lenght no equal')
else:
print('Not supported')
#重载运算符-def__sub__(self, other):
# 数组元素与数字other做减法，得到一个新数组pass#重载运算符*def__mul__(self, other):
#数组元素与数字other做乘法，或者两个数组相乘，得到一个新数组passdef__truediv__(self, other):
passdef__floordiv__(self, other):
passdef__pow__(self, power, modulo=None):
passdef__mod__(self, other):
pass#重载数组len，支持对象直接使用len()方法def__len__(self):
returnlen(self.__value)
#支持使用print()函数查看对象的值def__str__(self):
returnstr(self.__value)
def__contains__(self, n):
ifninself.__value:
returnTruereturnFalsedefdot(self,v):
ifnotisinstance(v,MyNArrays):
print('must be an instance of MyNArrays.')
returniflen(v)!=len(self.__value):
print('size must be equal.')
returnreturnsum([i*jfori,jinzip(self.__value,v.__value)])
#让本类具有修改数组元素的功能def__setitem__(self, key, value):
length=len(self.__value)
ifisinstance(key,int) and0<=key<length:
self.__value[key]=valueelse:
return'index error'#获取数组元素   def__getitem__(self, key):
length=len(self.__value)
ifisinstance(key, int) and0<=key<length:
returnself.__value[key]
else:
return'index error'#向数组中添加元素   defappend(self,n):
ifisinstance(n,(int,float)):
self.__value.append(n)
else:
print('isinstance error')
def__repr__(self):
returnrepr(self.__value)

a=MyNArrays(1,2,3,4,5,6)
b=MyNArrays(7,8,9,10,11,12)
print('数组a：',a)
print('数组b：',b)

print('a+b：',a+b)
print('a和b的内积为：', a.dot(b))

print('2是否为a的元素：',2ina)
a.append(17)
print('a添加元素17：',a)
print('查看a的第3各元素值：',a[2])
a[6]=15print('修改最后一项值为15：',a)