Area is a quantity that expresses the extent of a two-dimensional surface or shape, or planar lamina, in the plane.

learn more… | top users | synonyms

4
votes
2answers
2k views

How to find the area of raster values within polygon zones?

I'm using ArcGIS 9.3 and I just can't seem to get this right - I've tried tabulate areas, zonal stats, converting to polygons, etc. I'm missing something somewhere. I have a USGS impervious surface ...
4
votes
2answers
324 views

Total newbie. Creating map from aerial photo of golf course in QGIS

I have a aerial photo in tif with a tfw file of the golf course that I work at. I would like to create vector data of different features on the course such as greens fairways tees, etc. to calculate ...
2
votes
1answer
896 views

Area units for GEOS area property?

I'm working with GeoDjango and have a polygon in the WGS84 projection. I need to find its area in square meters. When I call polygon.area, I get some float out and I have no idea what the units of ...
6
votes
2answers
3k views

Openlayers geometry: how to convert area from degrees to square kilometres?

I get a multypolygon from my web service and want to calculate the area of that polygon. I was trying to use this piece of code: var poly = new OpenLayers.Geometry.MultiPolygon(poligon); var area = ...
5
votes
1answer
322 views

Geometry Calculation

Wanted to ask about accuracy of areas calculated by GIS compared to actual ones on ground. Because I have data of my country without areas for the districts within Uganda. Are the areas obtained using ...
4
votes
4answers
6k views

How to recalc WGS84 Shape_Area field to square miles in ArcGIS 10

What are the units of the Shape_Area field in a wgs84 feature class? Is it decimal degree squared? I would like to convert that to something more meaningful like square miles without reprojecting the ...
6
votes
1answer
96 views

Dividing the world space to geographic sub-space

I am trying to divide the world space to geographic sub-space from "general" to "specific" locations and without using latitude and longitude information. That is, I am trying to think about the world ...
3
votes
3answers
729 views

Overlay polygons on raster colour map to extract area values for each colour within each polygon

Does anyone know an answer to the following: I have a set of polygons created as the MCP of animal movements. I also have a habitat colour map raster, with 13 different habitat types as different ...
3
votes
3answers
13k views

Calculate projected area of polygons with field calculator in ArcMap 10

I've got a polygon featurelayer in arcmap. The coordinate system of the featurelayer's featureclass is web mercator. The dataframe of the map uses an equal-area projected coordinate system. I've ...
5
votes
2answers
3k views

Converting Longitude and Latitude Coordinates to Square Miles?

I have a set of Long and Lat co-ordinates making up a five point polygon which I have converted in excel using the following formula: ...
1
vote
4answers
4k views

Sum of areas in all each polygon layer?

I've got several layers/feature classes in an ArcMap 10 project. Thanks to everyone's help, I'm able to get the areas for the polygons contained within each layer. By opening the attribute tables ...
3
votes
2answers
7k views

Cannot get areas for polygon layers in ArcMap 10

For an ArcGIS project opened in ArcMap 10, we have added polygon layers representing different geographical features. After all the polygons were created, we opened the attribute tables for those ...
6
votes
0answers
696 views

How to split polygons without ArcView? [closed]

I'm trying to split polygons into equal areas. While fishnet sort of works; the areas I'm trying to split don't touch; they're national parks. Fishnet spans the whole area, not just the polygons in ...
11
votes
5answers
6k views

How can I measure area from geographic coordinates?

If I have polygons in geographic coordinates (WGS84), how do I measure the total area each takes on the surface of the earth, taking into account the curvature of the earth?