Polygon

Polygons may be characterised by their degree of convexity: Convex: any line drawn through the polygon (and not tangent to an edge or corner) meets its boundary exactly twice. Non-convex: a line may be found which meets its boundary more than twice.

Polygon-on-Polygon Overlay Difference between a Topologic Overlay and a Graphic Over plot ...

Polygons: An area fully encompassed by a series of connected lines. Because lines have direction, the system can determine the area that falls within the lines comprising the polygon. Polygons are often an irregular shape.

Polygon Split Merge Any polygonal feature can be split and merged with the new split and merge tools. Any rules that are defined in the Bentley Map project will be applied to the resulting attributes.

Polygones de toundra Definition An area of land in permafrost regions, in which the land surface has cracked and separated, forming polygon-shaped islands with ice wedges between them ...

polygon A feature used to represent areas. A polygon is defined by the lines that make up its boundary and a point inside its boundary for identification. Polygons have attributes that describe the geographic feature they represent.

polygon See Also : polygon feature, ring [data models] On a map, a closed shape defined by a connected sequence of x,y coordinate pairs, where the first and last coordinate pair are the same and all other pairs are unique.

Polygon- 2 dimensional vector object (i.e., has area). Polygons are defined by a set of arcs with a common topology. Projection- A model of the Earths surface for mapping (usually in 2 dimensions).

Polygon Inside This is ambiguous, so we state it in words: when performing a spatial join, ArcView will: ...

Polygon: A coverage used to represent areas. A polygon is defined by the arcs that make up its boundary. Polygons have attributes that describe the geographic feature they represent.

Polygon A coverage feature class used to represent areas. A polygon is defined by the arcs that make up its boundary and a point inside its boundary for identification.

polygon A multisided figure that represents area on a map. A feature defined by the arcs that make up its boundary. Every polygon contains one label point within its boundary.

POLYGON An area bounded by a closed line. It is used to describe spatial elements, such as housing and industrial units, administrative and political districts, and areas of homogeneous land use and soil types.

Polygonal structures of varying sizes appear on Mars. Some consider these to be volcanic in origin (see next page); others cite them as related to ice-produced features in deposits related to glaciation. This martian surface shows smaller polygons: ...

Polygon - An object in a map formed by a arc closing to itself, or by a multiple of arcs joining together. Polygons are also referred to as Areas or Area features.

TYPE: POLYGON Data downloadable from SJRWMD. Abstract: Wetands and Vegetation for Volusia County. This layer was downloaded from St Johns River Water Management District and not maintained by the County Environmental Staff.

Vector polygon data draped on the surface of the globe. The ArcGlobe application in ArcGIS 3D Analyst is designed to integrate extremely large amounts of GIS data and to allow fast navigation of this data.

In terms of polygons, the geographic centre or the average of the x and y values making up the perimeter points.

A Word About Polygons At this time, Google Maps does not provide the ability to generate true polygons, but I suspect that this will change in the near future as the API becomes more robust.

Clipping an Ocean Polygon When building a geographic database representing a coastal area, your census data and your digital elevation model will extend beyond the shoreline and make it difficult to make maps that look decent.

Conformal maps on polygons by Lee and Adams Several conformal maps in polygons and polyhedra. Usually nonconformal at polygon vertices Xarax's world in half a hexagon ...

In geographical terms, discrete data can be represented by polygons. Sometimes referred to as integer data. In contrast, see continuous data. Dot map Simple thematic technique using dots to show the spatial distribution of a chosen element.

These features can resemble circles, polygons, nets, steps, and stripes. The development of some of these shapes is thought to be the result of freeze-thaw action. Peak Annual Flow The largest discharge produced by a stream during a one year period.

Buffer: A polygon enclosing an area within a specified distance from a point, line or polygon. Accordingly, there are point buffers, line buffers and polygon buffers.

Analytical technique to determine whether a set of areas (polygons) are situated next to each other and to examine their interrelationships. network analysis.

Lines are constructed from strings of points, and polygons (regions) are built from lines which close.

For example, cities on a map of the world would be represented by points rather than polygons. No measurements are possible with point features.

In topological models (Fig. 6), a polygon is defined by a series of arcs. Arcs begin and end at nodes, which occur wherever two or more arcs meet.

The test network observed should be a polygon with station spacing not less than 50 meters and not more than 10 kilometers.

Geographic data representing each of the three possible vector types (points, lines, and polygons) of the earth's surface can be found in the SRP GIS.

Centroid - The geometric center of a polygon. Chi-Square - Rather than measuring the value of each of a set of items, ...

The data purchase does not include base polygons. Depending on geographic scale desired, however, base polygons at the census tract level and above are included with the purchase price of Maptitude GIS.

Attributes are data that describe the properties of a point, line, or polygon record in a Geographic Information System. For example, imagine a GIS coverage in which points represent sites on a landscape.

Map data includes points, lines, and polygons. Points represent anything that can be described as an x, y location on the face of the earth, such as shopping centers, customers, utility poles, hospitals, or cellular towers.

Centroid is the term given to the center of an area, region, or polygon. In the case of irregularly shaped polygons, the centroid is derived mathematically and is weighted to approximate a sort of "center of gravity.

To avoid this problem, I create a rectangular polygon shapefile that encloses the entire extent of the map, using the clip feature of the Geoprocessing Wizard (under the "Tools" menu) to subtract everything except the sea.

I believe that the first vertex of the gring (polygon) is the upper left (northwest) which would be 33.9744N 35.4294E and they proceed in a clockwise direction so the southwest coordinate would be the last pair, in this case 33.3364N 35.4116E.

An area feature is commonly referred to as a polygon. Polygonal data is the most common type of data in natural resource applications.

In the vector model, information about points, lines, and polygons is encoded and stored as a collection of x,y coordinates. The location of a point feature, such as a well, can be described by a single x,y coordinate.

The moPointInPolygon is one of the search methods in SearchShape. It is used to return polygon features that contain the first coordinate of the search feature (ESRI, 1996b).

Use the coordinates with the generate command to generate a polygon coverage Calculate which quads will be needed Merge all available surrounding quads (up to 8 plus the quad itself) /* and re-clip the grid using the generated polygon coverage ...

By the mid-1970s, development of so phisticated polygonal-based GIS systems at ORNL were well under way.

For example, a line could represent either a road or river, and a land use polygon could be residential, commercial, or a recreational area. Nominal data are often labelled with numbers or letters, but these labels do not imply ranking.

Polygonal features, such as sales territories and river catchments, can be stored as a closed loop of coordinates.

Gardner, M. "Mathematical Games: On Tessellating the Plane with Convex Polygons." Sci. Amer. 232, 112-117, Jul. 1975. Gardner, M. The Last Recreations: Hydras, Eggs, and Other Mathematical Mystifications. New York: Springer-Verlag, p. 86, 1997.

The point at which areas (lines, chains, strings) in a polygon network are joined. Nodes carry information about the topology of the polygons. Overlay: ...

The Geological Survey of Canada has published about 400 maps digitally. The geological polygons for approximately 250 of these maps are currently being made available to find, preview, and download as shape files through this map search tool.

mud cracks Cracks, generally polygonal, caused by the shrinking of a deposit of clay or silt under surface conditions. mudflow Form of mass movement similar to a debris flow but containing less rock material.

Topology - Topology is a mathematical procedure for explicitly defining spatial relationships. Topology expresses different types of spatial relationships as features (e.g., polygon features for areas and lines for linear features).

34 a directed set of non-intersecting line segments with nodes at each end and reference to left and right polygons. choropleth framework p.

[LINK] Because of map resolution and the limits of precision in digitizing, the very small polygons (areas) may not have all of the characteristics analyzed, so another GIS function was used to screen out areas smaller than 10 acres.

See also: Feature, Information, Map, Image, GIS