whole_func_string: function mahonyAHRSupdateIMU(gx, gy, gz, ax, ay, az) {
      let recipNorm;
      let halfvx, halfvy, halfvz;
      let halfex, halfey, halfez;
  
      // Compute feedback only if accelerometer measurement valid (afunctions NaN in accelerometer normalisation)
      if (ax !== 0 && ay !== 0 && az !== 0) {
        // Normalise accelerometer measurement
        recipNorm = (ax * ax + ay * ay + az * az) ** -0.5;
        ax *= recipNorm;
        ay *= recipNorm;
        az *= recipNorm;
  
        // Estimated direction of gravity and vector perpendicular to magnetic flux
        halfvx = q1 * q3 - q0 * q2;
        halfvy = q0 * q1 + q2 * q3;
        halfvz = q0 * q0 - 0.5 + q3 * q3;
  
        // Error is sum of cross product between estimated and measured direction of gravity
        halfex = ay * halfvz - az * halfvy;
        halfey = az * halfvx - ax * halfvz;
        halfez = ax * halfvy - ay * halfvx;
  
        // Compute and apply integral feedback if enabled
        if (twoKi > 0.0) {
          integralFBx += twoKi * halfex * recipSampleFreq; // integral error scaled by Ki
          integralFBy += twoKi * halfey * recipSampleFreq;
          integralFBz += twoKi * halfez * recipSampleFreq;
          gx += integralFBx; // apply integral feedback
          gy += integralFBy;
          gz += integralFBz;
        } else {
          integralFBx = 0.0; // prevent integral windup
          integralFBy = 0.0;
          integralFBz = 0.0;
        }
        // Apply proportional feedback
        gx += twoKp * halfex;
        gy += twoKp * halfey;
        gz += twoKp * halfez;
      }
  
      // Integrate rate of change of quaternion
      gx *= 0.5 * recipSampleFreq; // pre-multiply common factors
      gy *= 0.5 * recipSampleFreq;
      gz *= 0.5 * recipSampleFreq;
      const qa = q0;
      const qb = q1;
      const qc = q2;
      q0 += -qb * gx - qc * gy - q3 * gz;
      q1 += qa * gx + qc * gz - q3 * gy;
      q2 += qa * gy - qb * gz + q3 * gx;
      q3 += qa * gz + qb * gy - qc * gx;
  
      // Normalise quaternion
      recipNorm = (q0 * q0 + q1 * q1 + q2 * q2 + q3 * q3) ** -0.5;
      q0 *= recipNorm;
      q1 *= recipNorm;
      q2 *= recipNorm;
      q3 *= recipNorm;
    }
func_code_string: function mahonyAHRSupdateIMU(gx, gy, gz, ax, ay, az) {
      let recipNorm;
      let halfvx, halfvy, halfvz;
      let halfex, halfey, halfez;
  
      // Compute feedback only if accelerometer measurement valid (afunctions NaN in accelerometer normalisation)
      if (ax !== 0 && ay !== 0 && az !== 0) {
        // Normalise accelerometer measurement
        recipNorm = (ax * ax + ay * ay + az * az) ** -0.5;
        ax *= recipNorm;
        ay *= recipNorm;
        az *= recipNorm;
  
        // Estimated direction of gravity and vector perpendicular to magnetic flux
        halfvx = q1 * q3 - q0 * q2;
        halfvy = q0 * q1 + q2 * q3;
        halfvz = q0 * q0 - 0.5 + q3 * q3;
  
        // Error is sum of cross product between estimated and measured direction of gravity
        halfex = ay * halfvz - az * halfvy;
        halfey = az * halfvx - ax * halfvz;
        halfez = ax * halfvy - ay * halfvx;
  
        // Compute and apply integral feedback if enabled
        if (twoKi > 0.0) {
          integralFBx += twoKi * halfex * recipSampleFreq; // integral error scaled by Ki
          integralFBy += twoKi * halfey * recipSampleFreq;
          integralFBz += twoKi * halfez * recipSampleFreq;
          gx += integralFBx; // apply integral feedback
          gy += integralFBy;
          gz += integralFBz;
        } else {
          integralFBx = 0.0; // prevent integral windup
          integralFBy = 0.0;
          integralFBz = 0.0;
        }
        // Apply proportional feedback
        gx += twoKp * halfex;
        gy += twoKp * halfey;
        gz += twoKp * halfez;
      }
  
      // Integrate rate of change of quaternion
      gx *= 0.5 * recipSampleFreq; // pre-multiply common factors
      gy *= 0.5 * recipSampleFreq;
      gz *= 0.5 * recipSampleFreq;
      const qa = q0;
      const qb = q1;
      const qc = q2;
      q0 += -qb * gx - qc * gy - q3 * gz;
      q1 += qa * gx + qc * gz - q3 * gy;
      q2 += qa * gy - qb * gz + q3 * gx;
      q3 += qa * gz + qb * gy - qc * gx;
  
      // Normalise quaternion
      recipNorm = (q0 * q0 + q1 * q1 + q2 * q2 + q3 * q3) ** -0.5;
      q0 *= recipNorm;
      q1 *= recipNorm;
      q2 *= recipNorm;
      q3 *= recipNorm;
    }
func_documentation_string: --------------------------------------------------------------------------------------------------- IMU algorithm update