Resolve "Enable Standard Point Positioning (SPP) computation"

Closes #2 (closed)

include/gnss_utils/gnss_utils.h

@@ -4,6 +4,11 @@
 #include <vector>
 #include <iostream>
 #include <memory>
+
+#include <eigen3/Eigen/Dense>
+#include <eigen3/Eigen/Geometry>
+#include <eigen3/Eigen/Sparse>
+
 #include "observations.h"
 #include "navigation.h"
 
@@ -14,6 +19,27 @@ extern "C"
 
 namespace GNSSUtils
 {
-  static int getPos(Observations obs, Navigation nav, sol_t sol);
+  struct getPosOutput{
+    time_t time;
+    double sec;
+    Eigen::Vector3d pos;        // position (m)
+    Eigen::Vector3d vel;        // velocity (m/s)
+    Eigen::Matrix3d pos_covar;  // position covariance (m^2)
+                                // {c_xx,c_yy,c_zz,c_xy,c_yz,c_zx}
+    Eigen::VectorXd rcv_bias;   // receiver clock bias to time systems (s)
+    int type;                   // type (0:xyz-ecef,1:enu-baseline)
+    int stat;                   // solution status (SOLQ_???)
+    int ns;                     // number of valid satellites
+    double age;                 // age of differential (s)
+    double ratio;               // AR ratio factor for valiation
+
+    int pos_stat;               // return from pntpos
+    Eigen::Vector3d lat_lon;     // latitude_longitude_altitude
+  };
+
+  GNSSUtils::getPosOutput getPos(const std::shared_ptr<Observations> & _observations,
+                                const std::shared_ptr<Navigation> & _navigation);
+
+  Eigen::Vector3d ecefToLatLon(const Eigen::Vector3d & _ecef);
 }
 #endif