说明：  相机和地标用图形节点表示。相机坐标->相机的姿势，6载体 数据（相机）->指数为状态向量或[ ]如果一个固定镜头的坐标（地标）->地标位置，第一3元素6矢量数据（地标）->指数为状态向量
(The camera and the landmark are represented by a graphical node. The camera coordinates - > camera position, 6 carrier Data (camera) - > index is a state vector or [] if a fixed lens coordinates (landmark) - > landmark position, the first 3 element 6 vector data (landmark) - > index is the state vector)