/* Code fragments for fusion of an Euler yaw measurement from a 321 sequence. */ // calculate observation jacobians float t2 = q0*q0; float t3 = q1*q1; float t4 = q2*q2; float t5 = q3*q3; float t6 = t2+t3-t4-t5; float t7 = q0*q3*2.0f; float t8 = q1*q2*2.0f; float t9 = t7+t8; float t10 = 1.0f/(t6*t6); float t11 = t9*t9; float t12 = t10*t11; float t13 = t12+1.0f; float t14 = 1.0f/t13; float t15 = 1.0f/t6; H_YAW[0] = 0.0f; H_YAW[1] = t14*(t15*(q0*q1*2.0f-q2*q3*2.0f)+t9*t10*(q0*q2*2.0f+q1*q3*2.0f)); H_YAW[2] = t14*(t15*(t2-t3+t4-t5)+t9*t10*(t7-t8)); /* Code fragments for fusion of an Euler yaw measurement from a 312 sequence. */ // calculate observation jacobian float t2 = q0*q0; float t3 = q1*q1; float t4 = q2*q2; float t5 = q3*q3; float t6 = t2-t3+t4-t5; float t7 = q0*q3*2.0f; float t10 = q1*q2*2.0f; float t8 = t7-t10; float t9 = 1.0f/(t6*t6); float t11 = t8*t8; float t12 = t9*t11; float t13 = t12+1.0f; float t14 = 1.0f/t13; float t15 = 1.0f/t6; H_YAW[0] = -t14*(t15*(q0*q2*2.0f+q1*q3*2.0f)-t8*t9*(q0*q1*2.0f-q2*q3*2.0f)); H_YAW[1] = 0.0f; H_YAW[2] = t14*(t15*(t2+t3-t4-t5)+t8*t9*(t7+t10));