Coordinate Systems and Map Projections
There are several ways to refer to a coordinate system. Some people casually refer to any coordinate system as a "projection", but this is not strictly true.
Coordinate systems and projections are fundamental elements of mapping. These result from the need to reproject the earth's round shape [technically a geoid, not a sphere] on a flat plane.
Coordinate Systems
Once map data are projected onto a planar surface, features must be referenced by a planar coordinate system.
Coordinate Systems
General.
As described under map projections, traditional coordinate systems are based on a flat coordinate system.
The Coordinate System Inherent in your Data The geometry in GIS datasets is either encoded as vertices with coordinates, ...
coordinate systems based on a global scale where the size of the area is 10,000 km and the resolution is 1 mm would need 10 decimal digits or 30 binary digits
this will require double precision coordinates, which few GIS systems offer ...
[coordinate systems] A group of planar coordinate systems based on the division of the United States into more than 130 zones to minimize distortion caused by map projections.
Projected Coordinate System Management
Bentley PowerMap Field handles data in standard or customized projected coordinate systems. This capability allows you to combine data of dissimilar projections to conform to your map projection standards.
Cartesian coordinate system with the circle of radius 2 centered at the origin marked in red. The equation of the circle is x2 + y2 = 22.
Projected Coordinate Systems
During the time that Sir Issac Newton (and others) brought to the shape of the earth into public light in the early 18th century, topographic surveys of large regions were carried out.
Using the Latitude Longitude Coordinate System
The latitude longitude coordinate system uses angular measurements to describe a position on the surface of the earth.
Coordinate System
A reference system for defining points on the earth's surface. A coordinate system can be planar (flat) or nonplanar (spherical). The Cartesian system (x,y) is an example of a planar coordinate system.
coordinate system - A system to measure horizontal and vertical distances so that a geographic feature true position can be established in relation to an accepted public reference system such as State Plane or Universal Transverse Mercator (UTM) ...
coordinate system
A reference system used to measure horizontal and vertical distances on a planimetric map.
Coordinate System - A fixed reference framework superimposed onto the surface of an area to designate the position of a point within it by using x and y coordinates.
Coordinate Systems
Latitudes and Longitudes
Although the Earth is a three-dimensional object, when supposed spherical its surface has a constant radius, so any point on it is uniquely identified using a polar two-coordinate system.
Coordinate Systems: A framework used to define the positions (locations) of points in space either in two or three dimensions.
Coordinate System
The system used to measure horizontal and vertical distances on a planimetric map. A common coordinate system is used to spatially register geographic data for the same area.
Coordinate system : A system that allows a position to be located in two-dimensional space. It has an origin, two axes and a unit of measurement ...
Coordinate system - "A reference system for the unique definition of a location of a point in n-dimensional space" (Bonham-Carter, 1994, p. 355).
coordinate system
an exact definition of a system of mathematics and geodetic constants that defines how a specific geographic location is converted to a set of two or three numbers (for example, an X- and Y-value [and possibly a Z-value]); ...
Coordinate System
A particular kind of reference frame or system, such as plane rectangular coordinates or spherical coordinates, ...
UTM Coordinate System, based on the Universal Transverse Mercator map projection, is a planar locational reference system which provides positional descriptions accurate to 1 meter in 2,500 across the entire earth's surface except the poles.
Plane coordinate systems are used to locate data on the map plane. E.g. any point on the map plane can be located by means of two-dimensional cartesian (or rectangular) coordinates (x,y) or two-dimensional polar coordinates ( a,d ).
Polar coordinate system
The polar coordinate system is a coordinate system in the plane based on the selection of a point, designated as the origin of the system, ...
[edit] Coordinate systems in space
The locations of points in three-dimensional space are most conveniently described by three cartesian or rectangular coordinates, X,Y and Z.
Planar Coordinate System: A coordinate system drawn on a flat surface, or plane. Planar coordinates are usually expressed as pairs of rectangular X,Y values.
Earth's Coordinate System
The first step in converting the information contained in the real-world onto a 'piece of paper' was to devise a system where everything could be uniquely located in that world.
In your Coordinate Systems folder go to Geographic Coordinate Systems > North America > North American Datum 1983.prj and Click OK.
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Coordinate systems Imaginary grids superimposed on the earth's surface that can be used to reference the exact or absolute location of a feature on the earth.
Coordinate system - A system used to register and measure horizontal and vertical distances on a map.
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A coordinate system must have a point of origin and each location must be stated in terms of direction and distance from this point.
The Coordinate System Overview is an exellent overview of why various coordinate systems and datums exist.
The coordinate system (longitude and latitude) is still needed to create the map, but it is not shown on the face of the map.
If a coordinate system cannot be determined by reading the source data, it needs to be specified before any other action can be taken. This is where the coordinate system library comes into play.
Esri coordinate system definition files (.prj) are included.
ArcGIS for AutoCAD identifies attribute information from GIS features to give you full context of the surrounding environment.
A grid coordinate system that projects global sections onto a flat surface to measure position in specific zones.
User segment
The component of the GPS system that includes the receivers.
If the coordinate system arbitrarily affects the surface fit, then any arbitrary origin (translation) and rotation of the output space would effectively change the model.
The photo coordinate system origin is the so-called calibrated principal point (PP, Principal Point of Symmetry) which is in the center of the image. The origin of the axes is at the intersection of the radii traced from the fiducial marks.
A new geo-coordinate system conversion function (Edit/Geo Coord Convert/State Plane and LL) to convert between state plane coordinate system and the lat/long system. This function supports both NAD27 and NAD83 for all states in the US.
State Plane Coordinate System(s)
SPDK
Sistem Pengurusan Data Kadaster (Malaysia) ...
geographical coordinate system
A geographical coordinate system is a system that uses latitude and longitude to describe points on the spherical surface of the globe.
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Celestial coordinate systems
Delambre in his Histoire de l'Astronomie Ancienne (1817) concluded that Hipparchus knew and used a real (celestial) equatorial coordinate system, ...
Maling, D. H. Coordinate Systems and Map Projections-2nd edition. Oxford: Pergamon Press, 1992.
McDonnell, Porter W. Jr. Introduction to Map Projections. New York: Marcel Dekker, 1979.
Maling, D. H. Coordinate Systems and Map Projections, 2nd ed, rev. Woburn, MA: Butterworth-Heinemann, 1993.
Snyder, J. P. Flattening the Earth: Two Thousand Years of Map Projections. Chicago, IL: University of Chicago Press, 1993.
The state plane coordinate system (SPCS) is similar to the UTM system in many respects, but it does have some important differences. In the SPCS, each state has its own zone(s).
UTM Coordinate System (Universal Tranverse Mercator) A planar locational reference system which provides positional descriptions accurate to 1 meter in 2,500 across the entire earth`s surface except the poles.
The result is a coordinate system of columns (X), rows (Y), and verticals (Z) defining an imaginary matrix of grid elements, or "voxels," that are a direct conceptual extension of the "pixels" in a 2D raster image.
Eastings The x-coordinates in a plane coordinate system; see northings. Edge Match An editing procedure to ensure that all features crossing adjacent map sheets have the same edge locations attribute descriptions, and feature classes.
Easting First measurement of a grid reference used to specific the location of a point on a rectangular coordinate system. The distance measured eastward from the origin of a rectangular coordinate system.
Coordinate System: A recognized reference system for the unique location of a point in space. The Cartesian co-ordinate system and the system of latitude and longitude of the earth are examples of coordinate systems based upon Euclidean geometry.
Cartesian coordinate system A two-dimensional, planar coordinate system in which x measures horizontal distance and y measures vertical distance. Each point on the plane is defined by an x,y coordinate.
Feature classes can be found in a feature dataset where the same coordinate system can be shared and organized into a geometric network that can maintain topological relationships between its feature classes.
The circle on the left depicts a sphere with a radius r1 on which a coordinate system (essentially, latitude and longitude lines) has been traced. That describes expansion from an initial point (radius r0).
The spatial data types are referenced to a location by a standard system of coordinates, such as UTM (see Box 1), or by a local coordinate system.
standard-accuracy adjustment See: adjustment, standard-accuracy state plane coordinate system Coordinate systems established by the U.S.
A LOCATION is some geographic extent of interest that contains data sets that [should] all be in the same coordinate system.
It supported a national coordinate system that spanned the continent, coded lines as "arcs" having a true embedded topology, and it stored the attribute and locational information in separate files.
Since some maps may be from different resources, their coordinate systems could be different. Although ArcView provides some abilities to show maps in different projections, it does not change their coordinate systems.
A GIS references real-world spatial data elements (also known as graphic or feature data elements) to an coordinate system. These features can be separated into different layers (a.k.a. map themes or coverages).
 See also: Coordinate, Information, Map, Geographic, GIS
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