continuous.py 文件源码

def _get_M(self,delta_t):
        n=len(self.a)
        A=np.zeros(n)
        for i,ai in enumerate(self.a):
            Ae=[self.a[i]*(-1)**j*math.factorial(i)/math.factorial(j)/math.factorial(i-j)/((delta_t)**i) for j in range(i+1)]# Elementery A to assemblate in A
            for j,aej in enumerate(Ae):
                A[j]+=aej

        n=len(self.b)
        B=np.zeros(n)
        for i,ai in enumerate(self.b):
            Be=[self.b[i]*(-1)**j*math.factorial(i)/math.factorial(j)/math.factorial(i-j)/((delta_t)**i) for j in range(i+1)]# Elementery A to assemblate in A
            for j,bej in enumerate(Be):
                B[j]+=bej

        Mo=[-x/B[0] for x in B[1:][::-1]]
        Mi=[x/B[0] for x in A[::-1]]
        return (Mi,Mo)