''' mbinary ######################################################################### # File : polynomial.py # Author: mbinary # Mail: zhuheqin1@gmail.com # Blog: https://mbinary.xyz # Github: https://github.com/mbinary # Created Time: 2018-05-19 23:07 # Description: ######################################################################### ''' #!/bin/python3 # notice that creating a class's initialization won't conflict with __call__ method # because the former call class ,and the latter call instance # to be implemented class polynomial: pls = [] n = 0 def dictize(pl): if isinstance(pl, int) or isinstance(pl, float): pl = {0: pl} if isinstance(pl, polynomial): pl = pl.polynomial.copy() return pl def isZero(n): return abs(n) < 0.000001 def __init__(self, s='0 0'): polynomial.pls.append(self) polynomial.n += 1 if isinstance(s, polynomial): self.polynomial = s.polynomial.copy() # don't write like this .**self.polynomial = s.polynomial**,it's ref return elif isinstance(s, dict): self.polynomial = s.copy() return s = s.replace(',', ' ') s = s.replace('x', ' ') s = s.replace('x^', ' ') s = s.replace(':', ' ') s = s.replace('\n', ' ') s = s.split(' ') num = len(s) i = 0 print(s) self.polynomial = dict() li = [float(i) for i in s] while i < num: if not polynomial.isZero(li[i]): index = li[i+1] if index in self.polynomial.keys(): self.polynomial[index] += li[i] else: self.polynomial[index] = li[i] i += 2 if not self.polynomial: self.polynomial = {0: 0} def __iter__(self): return iter(list(self.polynomial.keys())) def __getitem__(self, key): return self.polynomial[key] def __setitem__(self, key, val): self.polynomial[key] = val def __delitem__(self, k): del self.polynomial[k] def __add__(self, pl): pl = polynomial.dictize(pl) rst = self.polynomial.copy() for i in pl: if i not in rst: rst[i] = pl[i] else: rst[i] += pl[i] if polynomial.isZero(rst[i]): del rst[i] return polynomial(rst) def __iadd__(self, pl): pl = polynomial.dictize(pl) for i in pl: if i not in self: self[i] = pl[i] else: self[i] += pl[i] if polynomial.isZero(self[i]): del self[i] return self def __sub__(self, pl): pl = polynomial.dictize(pl) tmp = {i: -j for i, j in pl.items()} return self + tmp def __mul__(self, pl): pl = polynomial.dictize(pl) dic = dict() for i in pl: for j in self: index = i+j if index in dic: dic[index] += pl[i]*self[j] else: dic[index] = pl[i]*self[j] return polynomial({i: j for i, j in dic.items() if not polynomial.isZero(j)}) def __imul__(self, pl): self = self*pl return self def __pow__(self, n): rst = polynomial({0: 1}) for i in range(n): rst *= self.polynomial return rst def __repr__(self): return self.__str__() def __str__(self): output = '' if self.polynomial: key = sorted(self.polynomial.keys(), reverse=True) num = len(key) for j, i in enumerate(key): if polynomial.isZero(i): output += '%+g' % self[i] continue if not polynomial.isZero(self[i]-1): if not polynomial.isZero(self[i]+1): output += "%+g" % self[i] else: output += '-' else: output += '+' if not polynomial.isZero(i): output += 'x' if not polynomial.isZero(i-1): output += '^%g' % i if output[0] == '+': return output[1:] return output def iterPolynomial(self, s): rst = polynomial({0: 0}) for i in self: rst += s**int(i)*self[i] return rst def __call__(self, s): if isinstance(s, polynomial): return self.iterPolynomial(s) sum = 0 for i in self: sum += self[i] * s**i return sum def __xor__(self, n): tmp = polynomial(self) for i in range(n): self = self.iterPolynomial(tmp) return self def save(self): polynomial.pls.append(self) polynomial.n += 1 def delPlynomial(self, n): return polynomial.pls.pop(n-1) def menu(): print('polynomial operations') print('1.create') print('2.add') print('3.sub') print('4.iadd') print('5.mul') print('6.del') print('7.display') print('8.cal val') print('9.polynomial iter') print('10.menu') print('11.exit') if __name__ == '__main__': menu()