Python —将__init__与继承的方法用于多项式类

Question

这是一个类，它将作为输入，然后以字符串形式（两种格式相同）输出多项式。 在各种方法中执行一些算术运算。 我一直在尝试将该类继承为另一个类，该类随后将使用第一个类的__mod __（）特殊方法（或在必要时使其成为自己的特殊方法，但我看不到如何不能只使用原始类方法）对摄入量进行修改。 似乎是这样的__init __（），但是我尝试了5个不同的版本，甚至更改了父类，但我一无所获。 我正在自学Python，因此我敢肯定，即使是初级Python开发人员也可以看到我要去哪里完全错了。

import re

class GF2Polynomial(object): #classes should generally inherit from object

    def __init__(self, string):
        '''__init__ is a standard special method used to initialize objects.
        Here __init__ will initialize a gf2infix object based on a string.'''
        self.string = string  #basically the initial string (polynomial)
        self.key,self.lst = self.parsePolyVariable(string) # key determines polynomial compatibility
        self.bin = self.prepBinary(string)  #main value used in operations

    def id(self,lst):
        """returns modulus 2 (1,0,0,1,1,....) for input lists"""
        return [int(lst[i])%2 for i in range(len(lst))]

    def listToInt(self,lst):
        """converts list to integer for later use"""
        result = self.id(lst)
        return int(''.join(map(str,result)))

    def parsePolyToListInput(self,poly):
        """
        replaced by parsePolyVariable. still functional but not needed.
        performs regex on raw string and converts to list
        """
        c = [int(i.group(0)) for i in re.finditer(r'\d+', poly)]
        return [1 if x in c else 0  for x in xrange(max(c), -1, -1)]

    def parsePolyVariable(self,poly):
        """
        performs regex on raw string, converts to list.
        also determines key (main variable used) in each polynomial on intake
        """
        c = [int(m.group(0)) for m in re.finditer(r'\d+', poly)] #re.finditer returns an iterator
        letter = [str(m.group(0)) for m in re.finditer(r'[a-z]', poly)]
        m = max(c); varmatch = True; key = letter[0]
        for i in range(len(letter)):
            if letter[i] != key: varmatch = False
            else: varmatch = True
        if varmatch == False: return "error: not all variables in %s are the same"%a
        d = [1 if x in c else (1 if x==0 else (1 if x=='x' else 0))  for x in xrange(m, -1, -1)]
        return key,d

    def polyVariableCheck(self,other):
        return self.key == other.key

    def prepBinary(self,poly):
        """converts to base 2; bina,binb are binary values like 110100101100....."""
        x = self.lst; a = self.listToInt(x)
        return int(str(a),2)

    def __mod__(self,other):
        """
        __mod__ is the special method for overriding the % operator
        returns remainder formatted as polynomial
        """
        if self.polyVariableCheck(other) == False:
            return "error: variables of %s and %s do not match"%(self.string,other.string)
        if self.bin == other.bin: return 0
        return GF2Polynomial(self.outFormat(self.bin%other.bin))

    def __str__(self):
        return self.string

    def outFormat(self,raw):
        """process resulting values into polynomial format"""
        raw = "{0:b}".format(raw); raw = str(raw[::-1]); g = [] #reverse binary string for enumeration
        g = [i for i,c in enumerate(raw) if c == '1']
        processed = "x**"+" + x**".join(map(str, g[::-1]))
        proc1 = processed.replace("x**1","x"); proc2 = proc1.replace("x**0","1")
        if len(g) == 0: return 0 #return 0 if list empty
        return proc2  #returns result in gf(2) polynomial form

期望的结果是能够在具有父类型的新（子）类上调用它，同时尽可能少地更改父类（即使有改变）。 请注意，类“ BinaryField”是预期的子类：

p=GF2Polynomial("x**2+x**1+x**0")
a=BinaryField("x**1+x**0", p)
b=BinaryField("x**1", p)

进气时，给定的多项式应为模数除以第二个元素（此处为“ p”）。 这对于有限域数学是必需的。

编辑：用-运行它时

## "x**1 + x**0" polynomial string style input
poly1 = "x**14 + x**1 + x**0"; poly2 = "x**6 + x**2 + x**1"; poly3 = "y**6 + y**2 + y**1"
a = GF2Polynomial(poly1); b = GF2Polynomial(poly2); c = GF2Polynomial(poly3)
## "x+1" polynomial string style input
poly4 = "x**14 + x + 1"; poly5 = "x**6 + x**2 + x"; poly6 = "y**6 + y**2 + 1"
d = GF2Polynomial(poly4); e = GF2Polynomial(poly5); f = GF2Polynomial(poly6)
bf1 = BinaryField(poly1,b); print bf1
bf2 = BinaryField(poly4,e); print bf2

由于我的编码方式，这两种样式都是可能的，但它们都应返回相同的答案。 但是，该代码的结果是：

>>> 
x**5 + x**4 + x**3 + 1
x**5 + x

此外，当使用BinaryField（poly4，d）（与GF2Polynomial（）初始化是相同的字符串）时，出现以下错误： AttributeError: 'int' object has no attribute 'string'

Answer 1

这样可以解决您的问题吗？

class BinaryField(GF2Polynomial):
    def __init__(self, string, mod):
        modded = GF2Polynomial(string) % mod
        super(BinaryField, self).__init__(modded.string)


>>> p = GF2Polynomial("x**2+x**1+x**0")
>>> a = BinaryField("x**1+x**0", p)
>>> print a
x + 1

您还可以使BinaryField类只是一种工厂方法：

def BinaryField(string, mod):
    return GF2Polynomial(string) % mod