State Plane Coordinate System State Plane Coordinate System The State Plane Coordinate System (SPS or SPCS) is a set of 124 geographic zones or coordinate systems designed for specific regions of the United States. Each state contains one or more state plane zones, the boundaries of which usually follow county lines. There are 110 zones in the contiguous US, with 10 more in Alaska, 5 in Hawaii, and one for Puerto Rico and US Virgin Islands. The system is widely used for geographic data by state and local governments. Its popularity is due to at least two factors. First, it uses a simple Cartesian
Distance from a point to a plane the closest point to the origin may be expressed more succinctly using notation from linear algebra. The expression formula_19 in the definition of a plane is a dot product formula_20, and the expression formula_21 appearing in the solution is the squared norm formula_22. Thus, if formula_23 is a given vector, the plane may be described as the set of vectors formula_24 for which formula_25 and the closest point on this plane is the vector Written in Cartesian form, the closest point is given by formula_27 for formula_28 where and the distance from formula_30 to the hyperplane is Thus in formula_32