ignav的代码

static void updstat(const insopt_t *opt,insstate_t *ins,const double dt,
                    const double *x0,const double *P0,double *phi,double *P,
                    double *x,double *Q)
{
    opt->exprn?getprn(ins,opt,dt,Q): getQ(opt,dt,Q); // 

//phi 状态转移矩阵 ，离散化的公式代入，微分误差方程的系数矩阵
    opt->exphi?precPhi(opt,dt,ins->Cbe,ins->re,ins->omgb,ins->fb,phi):getPhi1(opt,dt,ins->Cbe,ins->re,ins->omgb,ins->fb,phi); 


    if (fabs(dt)>=MAXUPDTIMEINT) {
        getP0(opt,P);// 初始化
    }
    else {
        propP(opt,Q,phi,P0,P); // P的预测 pk/k-1 =  phi *P0* phiT +Q
    }

    if (x) propx(opt,x0,x);


    if (ins->P0) matcpy(ins->P0,P  ,ins->nx,ins->nx);
    if (ins->F ) matcpy(ins->F ,phi,ins->nx,ins->nx);
}