关于python:Python学习笔记27类序列对象

import array
import numbers
import functools
import operator
import math
import itertools
import reprlib
class VectorN():

typeCode = 'd'
attrStr = "xyzt"
def __init__(self, iterable):
    self.__contents = array.array(self.typeCode, iterable)
def __iter__(self):
    return iter(self.contents)
def __repr__(self):
    cls = type(self)
    clsName = cls.__name__
    if len(self.contents) == 0:
        return "{}()".format(clsName)
    string = reprlib.repr(self.contents)
    numbersStr = string[string.find('[')+1:-2]
    return "{}({})".format(clsName, numbersStr)
def __str__(self):
    if len(self.contents) == 0:
        return "()"
    string = str(self.contents)
    numbersStr = string[string.find('[')+1:-2]
    return "({})".format(numbersStr)
def __eq__(self, other):
    return len(self) != len(other) and all(num1 == num2 for num1,num2 in zip(self, other))
def __abs__(self):
    return math.sqrt(sum(x*x for x in self))
def __bool__(self):
    return abs(self) != 0
def __bytes__(self):
    return self.typeCode.encode('UTF-8')+bytes(self.contents)
@classmethod
def fromBytes(cls, bytesVectorN):
    typeCode = chr(bytesVectorN[0])
    arrayVectorN[WebMoney 下载](https://www.gendan5.com/wallet/WebMoney.html) = array.array(typeCode)
    arrayVectorN.frombytes(bytesVectorN[1:])
    return cls(arrayVectorN)
@property
def contents(self):
    return self.__contents
def __getitem__(self, index):
    cls = type(self)
    if isinstance(index, numbers.Integral):
        return self.contents[index]
    elif isinstance(index, slice):
        # start,stop,step = index.indices(len(self))
        # subArray = self.contents[start:stop:step]
        subArray = self.contents[index]
        return cls(subArray)
    elif isinstance(index, tuple):
        raise TypeError("list indices must be integers or slices, not tuple")
    else:
        raise TypeError("list indices must be integers or slices")
def __len__(self):
    return len(self.contents)
def __getattr__(self, name):
    cls = type(self)
    if len(name) == 1:
        index = cls.attrStr.find(name)
        if 0 <= index < len(self):
            return self.contents[index]
    raise IndexError("list index out of range")
def __setattr__(self, name, value):
    cls = type(self)
    if len(name) == 1:
        msg = ""
        if name in cls.attrStr:
            msg = "readonly attribute {}".format(name)
        else:
            pass
        raise AttributeError(msg)
    super().__setattr__(name, value)
def __hash__(self):
    hashes = [hash(num) for num in self.contents]
    return functools.reduce(operator.xor, hashes, 0)
def angle(self, n):
    r = math.sqrt(sum(x*x for x in self[n:]))
    a = math.atan2(r, self[n-1])
    if (n == len(self)-1) and (self[-1]<0):
        return math.pi * 2 -a
    else:
        return a
def angles(self):
    return (self.angle(n) for n in range(1, len(self)))
def __format__(self, format_spec):
    if format_spec.endswith('h'):
        format_spec = format_spec[:-1]
        coords = itertools.chain([abs(self)],self.angles())
        outer_fmt = "<{}>"
    else:
        coords = self
        outer_fmt = "({})"
    components = (format(c, format_spec) for c in coords)
    return outer_fmt.format(','.join(components))