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README.md

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 # GraphGNSSLib
-An Open-source Package for GNSS Positioning and Real-time Kinematic Using Factor Graph Optimization
+## An Open-source Package for GNSS Positioning and Real-time Kinematic Using Factor Graph Optimization
 This repository is the implementation of the open-sourced package, the GraphGNSSLib, which makes use of the factor graph optimization (FGO) to perform the GNSS positioning and real-time kinematic (RTK) positioning. In this package, measurements from the historical and current epochs are structured into a factor graph. The package is based on C++ which is compatible with the robot operation system (ROS) platform. The package will be released recently!