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Geometry (Greek γεωμε"ρία; geo = earth, metria = measure) is a part of mathematics concerned with questions of size, shape, and relative position of figures and with properties of space. Geometry is one of the oldest sciences.


geometry -
(1) [Euclidean geometry] The measures and properties of points, lines, and surfaces. In a GIS, geometry is used to represent the spatial component of geographic features.

Geometry and the Imagination in Minneapolis
John Conway Peter Doyle Jane Gilman Bill Thurston
June 1991
Version 0.91 dated 12 April 1994 ...

Geometry-symbol layer combinations
For example, adding a fill layer to a line representation rule would generate a warning because there is no polygon geometry to fill. To repair the logic, add a line-to-polygon geometric effect to either the fill layer or the global effects portion of the rule.

Close the geometry_columns table and right click the spatial_ref_sys table and select View Data View All Rows.

coordinate geometry traverse
[ESRI software] In Survey Analyst, a process of computing a sequence of survey point locations starting from an initial known point. Each new survey point is defined by a traverse course and is used as the takeoff point for the next point in the sequence.

Coordinate Geometry
Used to construct mathematical/geometric models of a design and its environment. See also COGO.

MAPEXPORT merges geometry
Issue:
You run a MAPEXPORT on some drawing features to put them into a GIS data format (SHP, SDF, or other). When looking at the resultant GIS data, the geometry looks the same, however the number of objects is different.

~ Converters
PostGIS with shp2pgsql:
shp2pgsql -D lakespy2 lakespy2 test lakespy2.sql
e00pg: E00 to PostGIS filter, see also v.in.e00.

~Geometry deals with the measures and properties of points, lines and surfaces. In ARC/INFO, ~ is used to represent the spatial component of geographic features.
georeferenceTo establish the relationship between page coordinates on a planar map and known real-world coordinates.

Civil Geometry tools are coordinate geometry (COGO) tools that utilize a heads-up interface, preserving user input and design intent. Results of these tools are intelligent graphic elements stored in the DGN. Civil Geometry includes: ...

Link (geometry): An element of geometry that connects nodes. In a polygon topology, a link defines a polygon edge. Links can contain vertices and true arcs, and can be represented as a line, polyline, or arc.

~ model (point, line, area)
~ operations (e.g., intersect, union, within, etc.)
Precision handling
Geometric constructions
Metric functions (e.g., Cartesian 2D distance, Hausdorff distance)
Spatial algorithms (e.g. buffer creation, line offsets, line simplification) ...

~ Alignment removes discrepancies between geometries.
Information Transfer involves updating one dataset with information from the other. This information can be either attributes or geometry to be added to an existing feature, or entire features to be added to the dataset.
...

~ of color elements of various CRT and LCD displays; phosphor dots in a color CRT display (top row) bear no relation to pixels or subpixels.

~ ratio
numeric values are proportional to the original area or length of the feature
Each field in the layer attribute table can have split policies applied.

~ Output functions - these are important particular for web-development when using the various javascript, flash apis
STAsBinary(), STAsText(), AsGML(), AsTextZM(), will have a builder api in the RTM for extending to support more output formats
Same as the geometry ones ...

~ is complex. The geometrical algorithms needed for polygon overlay and the calculation of distances, depending on the projection/coordinate system used, require experienced programmers. This is not usually a problem for most GIS users since most functions are directly coded in the software.

~ and topology; Greater than; Geologian Tutkimuskeskus = Geological Survey of Finland
G.T.
Gas tank ...

~; Imperial guards
G&M
Geography and Map; geography and Map Div.

The ~ of the earth has been discussed, studied, and imagined forever. The ancient Greek philosophers tried to picture a pure geometrical model.

The ~ of the thematic data is entirely or partially described by the base ~ dataset.
The thematic dataset holds information that also describes objects of the base dataset.

The ~ of GIS data is referenced in coordinates that are embedded in the data file. Shape files that you get from ESRI StreetMap and from the ESRI Data CDs use Latitude and Longitude as the coordinate system. This is known as a Geographic Coordinate System.

SDO_~
For a legacy coordinate system, the dimensional boundary (if any).
IS_VALID ...

In the geometry of the sphere, great circles play the part of straight lines. They represent the shortest distance between two points. Every great circle is determined by a plane that contains the center of the sphere.

About the Geometry of Datums
In order to calculate where latitudes and longitudes occur on the surface of the Earth a number of fundamental geometric concepts and practices need to be applied. In simple terms these include: ...

coordinate geometry (COGO) This refers to a data conversion process in which a digital map is constructed from written descriptions, such as legal descriptions of land parcel boundaries.

Coordinate geometry - The methods used to construct graphics mathematically in engineering design. It is usually referred to as COGO.

Coordinate system - A system used to register and measure horizontal and vertical distances on a map.

Coordinate Geometry - COGO
A method of defining geometric features through the input of bearing and distance measurements.

Coordinate Geometry
A third technique for the input of spatial data involves the calculation and entry of coordinates using coordinate geometry (COGO) procedures. This involves entering, from survey data, the explicit measurement of features from some known monument.

Computational Geometry
This is the discipline of developing efficient algorithms to solve problems of spatial analysis.
A GIS insulates the user from these details, but you need to understand the engineering principles of the algorithms in order to use the GIS well.

Figure 5-9. ~ of an EDM (Basic Example)
OBSERVATION PRECAUTIONS ...

Line ~Line Style A definition of color and width for lines drawn on a map. Synonyms: Line Styles Linear Grade Floating-point piecewise-linear interpolation used to calculate a weighted score a Factor. This is associated with a Grade System.

While the vector ~ has a large amount of models the raster model even with the newly added extensions [16] does not contain conceptually new ideas (not even the tesseral indexing is allowed).

COGO: CO-ordinate ~. Algorithms for handling basic two and three dimensional vector entities built into all surveying, mapping and GIS software. Co-ordinate Numbers representing the position of a point relative to an origin.

In ArcCatalog the ~ and data model is identified by an icon. Only file formats recognized by ArcCatalog as geographic data will be displayed. The handy table from Lab #1shows the icons and their associated "Type", the screenshot below shows ArcCatalog's view of a folder that contains GIS data.

AGG Anti-Grain ~ A high quality graphics rendering engine that MapServer 5.0+ can use. It supports sub-pixel anti-aliasing, as well as many more features. CGI Wikipedia provides excellent coverage of CGI. EPSG ...

Conventionally, the ~ of perspective conic projections is defined by a line connecting the center of the sphere to the tangency point (or the angular midpoint for the secant case), therefore normal to the mapping surface.

COGO - Coordinate ~: A set of procedures for encoding and manipulating bearings, distances and angles of survey data into co-ordinate data. COGO is frequently a subsystem of GIS.

A feature is not defined in terms of a single ~, but rather as a conceptually meaningful object within a particular domain of discourse, one or more of whose properties may be geometric.

31 basic components that are sufficient to build a larger system; the primitives of two-dimensional ~ are points, lines, and areas. projection p. 60 coordinate transformation that converts latitude longitude measurements into planar coordinates.

COGO See coordinate ~. Colour composite In remote sensing, a colour image composed of three bands projected in the red, point and green guns. Column A vertical field in a relational database management system data file. It may store one to many bytes of information.

Abbreviation of the term COordinate ~. Land surveyors use COGO functions to enter survey data, to calculate precise locations and boundaries, to define curves, and so on.
2. The name of the ArcInfo coordinate ~ software product. column The vertical dimension of a table.

The shape of Earth's surface or the ~ of landforms in a geographic area.
Trace Element:
An element that is present in very small quantities.
Traction: ...

Geodatabases support large collections of objects in a database table and features with ~. The feature classes and tables contained in geodatabases can be related to one another. In order to define the relationships between objects in a geodatabase, a relationship class must first be created.

Such a map database is a vector representation of a given road network including road ~ (segment shape), network topology (connectivity) and related attributes (addresses, road class, etc). Geographic Data Files (GDF) is an ISO standard for formulating map databases for navigation.

In GIS the shapes and locations of things are stored as coordinate ~. GIS data is often stored in a database, either storing the coordinates as numbers or using special ~ data types.

TopologyA set of rules that models the relationship between neighboring points, lines, and polygons and determines how they share ~. Topology is also concerned with preserving spatial properties when the forms are bent, stretched, or placed under similar geometric transformation.

View angle is an important component of the imaging ~. View angle and illumination ~ (solar zenith and azimuth angles) are important determinants of the measured reflectance since adjustments in observation and illumination ~ result in different sampling of the bidirectional ...

GPS receivers usually report the quality of satellite ~ in terms of Position Dilution of Precision, or PDOP. PDOP refers to horizontal (HDOP) and vertical (VDOP) measurements (latitude, longitude and altitude).

Because of the alignment limitations of the squares and cubes used in Cartesian ~, tomorrow's representation of continuous space likely will use regular hexagon and dodecahedral (12-sided volume) shapes as their ~ "nests" without gaps in representing our curved earth (2D circle; ...

By 1980, the Loran-C User Handbooks provided separate charts of coverage for each chain based on ~, noise, and signal strength. These charts assumed a three station, Master-Secondary- Secondary receiver.

Event features, the segmentation points, are not stored in the ~ of the coverage but are derived as needed.

DOP is an indicator of the quality of the ~ of the satellite constellation. Your computed position can vary depending on which satellites you use for the measurement. Different satellite geometries can magnify or lessen the errors in the error budget described above.

Geodatabases store ~, a spatial reference system, attributes, and behavioral rules for data. Various types of geographic datasets can be collected within a geodatabase, including feature classes, attribute tables, raster datasets, network datasets, topologies, and many others.

" These databases contain first the ~ element layer of the roadway that contains links, nodes, shape points, relative elevations, and connectivity.

GIS data used in the model can be raster, vector, textual and hybrid types from many diverse sources using state-of-the-art techniques: ~ from CAD systems; video and slide images; commercially available digital data (vector and/or raster); existing maps, charts, and drawings; ...

A measure of the GPS receiver/satellite ~. A low DOP value indicates better relative ~ and higher corresponding accuracy. The DOP indicators are GDOP (geometric DOP), PDOP (position DOP), HDOP (horizontal DOP), VDOP (vertical DOP), and tdOP (time clock offset).

Acronym for Coordinate ~, COGO is a subsystem of CAD or GIS made up of a set of standard procedures for processing survey data such as bearings, distances and angles to generate precise spatial representation of land features and survey control networks.
Commit ...

helpful in studying the effects of ~ and spatial arrangement of habitat
e.g. size and shape of woodlots on the animal species they can sustain
e.g. value of linear park corridors across urban areas in allowing migration of animal species
G. COMMANDS TO DESCRIBE CONTENTS OF LAYERS ...

A specific kind of area that involves a complex ~. This type of area is formed of inclusive and exclusive lines. Inclusive lines define the external delimitation of the area, while exclusive lines delimit the internal zones to be excluded. (Also known as complex polygon.)
Complex Feature ...

The earth is actually best approximated as an oblate spheroid, meaning that it is flattened at the poles, although this ~ does not quite describe its shape exactly either. The ~ of an ellipsoid is best expressed using spherical coordinates.

Once a DEM model is constructed for an area of interest, you may use this to model fault traces, find the ~ of Turbidity current deposits or validate existing models. Resolution of the DEM is determined by the images that it is constructed from.

" The first half of this chapter is devoted to geodesy and coordinate ~, both plane and earth. The second half of the chapter begins with an introduction to map projections. The projection process is explained as beginning with the geoid and ending with a reference globe.

[graphics (computing)] The process of drawing to a display; the conversion of the ~, coloring, texturing, lighting, and other characteristics of an object into a display image.
Map element ...

void polygon -- defines a part of the two-dimensional manifold that is bounded by other GT-polygons, but otherwise has the same characteristics as the universe polygon. The ~ and topology of a void polygon are those of a GT-polygon.

Allows attribute data to be associated with features;
Keeps georeferencing information with data - important if data will be added to future maps;
Very useful if ~ is for a specific area; and
Available for both Mac and PC platforms (Illustrator or Freehand).

The measure of how much the ~ of the satellites affects the horizontal position estimate.
L
LOI ...

Attribute labeling is another issue here. GIS and mapping data requires extensive attribute labeling to link graphical items to database, while CAD drawing are mostly shape and ~ oriented and spatial analysis is hardly done.

This allows end users in different parts of the world to make more accurate predictions of GPS performance in their particular location, taking into account regional effects of the atmosphere and satellite ~, as well as the effects of their particular user equipment.

As discussed earlier, the amount of insolation being received by a location on the Earth varies both spatially and temporally because of Sun-Earth ~, Earth rotation, and spatial differences in the Earth's atmospheric transparency.

This field represents the ~ of the features in the GeoDataset. The programmer can use "Shape" to get the collected spatial data and display it by the Map.DrawShape method. The attribute data can be displayed by Map.DrawText method.

Several optional extension products add application-specific tools to ARC/INFO, including: NETWORK (network modeling), TIN (surface modeling and terrain analysis), COGO (interactive coordinate ~ data entry and management), GRID (raster data analysis and management), ...

The Multipatch ~ Type [PDF]
Geographic Information Systems: Providing the Platform for Comprehensive Emergency Management [PDF]
ArcLogistics Desktop: The Routing and Scheduling Solution for Fleet Management [PDF]
Calibrating the Huff Model Using ArcGIS Business Analyst [PDF] ...

See also: See also: What is the meaning of Feature, Information, Model, Map, Analysis?

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