/* 卡爾曼濾波處理 */
double KalmanFilter(const double ResrcData,double ProcessNiose_Q,double MeasureNoise_R) //定義一個double類型的常變量(它的值不準修改)
{
double R = MeasureNoise_R;
double Q = ProcessNiose_Q;
static double x_last;
double x_mid = x_last;
double x_now;
static double p_last;
double p_mid ;
double p_now;
double kg;
x_mid=x_last; //x_last=x(k-1|k-1),x_mid=x(k|k-1)
p_mid=p_last+Q; //p_mid=p(k|k-1),p_last=p(k-1|k-1),Q=噪聲
/* 卡爾曼濾波的五個重要公式 */
kg=p_mid/(p_mid+R); //kg為kalman filter,R 為噪聲
x_now=x_mid+kg*(ResrcData-x_mid); //估計出的最優值
p_now=(1-kg)*p_mid; //最優值對應的covariance
p_last = p_now; //更新covariance 值
x_last = x_now; //更新系統狀態值
return x_now;
pressure=x_now;
}
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