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

1
vote
1answer
33 views

Calculate area weighted average of attribute in one layer by shape in another

For a project I am working on I would like to intersect fire station response districts with income data to determine the median income per response district. However the borders of the layers ...
0
votes
1answer
26 views

How to use Calculate Geometry tool to calculate area

I have added a field in my attribute table but I cannot calculate the area. The units field is greyed out and the options at the top say "area - disabled". What can I do about this?
2
votes
1answer
34 views

Create a grid with statistics of the merged shapefiles in QGIS

I operate with QGIS. I have to split the shape files of the buildings and the roads of a city into a grid of 500x500m per square and into each square I have to obtain the total free area, the total ...
3
votes
0answers
61 views

Why does field calculator compute area in square meters?

I am using EPSG:102748, and have set my Settings/Option preferred measurement units to ft. My CRS is NAD_1983_StatePlane_Washington_North_FIPS_4601_Feet, and when I use the measure tool, it returns ...
4
votes
1answer
57 views

Equal area projections with different area results in ArcGIS for Desktop?

Using ArcGIS, I have to calculate areas of huge polygons all over the Pacific Oceans betwwen 20N and 30S. I have been trying different Equal-areas projections (Cylindrical and sinusoidal for example) ...
0
votes
0answers
34 views

Is it possible to calculate area of polygons from GPS points without POSTGIS

I am new with GIS. Assume we use the UTM30N coordinate system. Is it possible to calculate an area (say a square box) by the 4 given points? (assume the points are in order, and the coordinates are ...
1
vote
2answers
44 views

Tabulate Area in ArcGIS for Desktop not creating correct output?

I have used the Tabulate Area zonal spatial analyst tool in ArcGIS many times, and am encountering a problem for the first time. I am using a polygon grid (fishnet) as my zone dataset, and tabulating ...
1
vote
0answers
33 views

Using Tabulate Area 2 update for ArcGIS

I am trying to use the "Tabulate Area 2" tool in the following update: http://blogs.esri.com/esri/arcgis/2013/11/26/new-spatial-analyst-supplemental-tools-v1-3/ I have overlapping polygons in which ...
1
vote
0answers
55 views

Calculating vector area in QGIS

I have calculated a viewshed (ZVI) in OpenWind and opened the raster in QGIS I have then converted the raster to a vector When I open the attribute table there are 4682 rows (features) and there is ...
0
votes
0answers
22 views

How can i perform area calculations in a raster file?

I would like to know if is possible and how can i calculate all areas or parts of it in one raster? Can i do it using the raster calculator? All help is appreciated, Best regards
3
votes
0answers
60 views

How to calculate areas in raster files

I got three files. The first is a shape file for country boundaries and the second and third are two raster files with the global land covers for 2005 and 2009. I'm thus encharged to calculate the ...
1
vote
3answers
85 views

Can I find out the exact areas which each category covers?

I have accessed a land use map and clipped the appropriate area I need to analyse. Is there a way I can find the exact areas which each category covers?
0
votes
1answer
21 views

Measuring roundness using buffers around centroids [duplicate]

I'm trying to measure the compactness (roundness) of some 800 polygons of different shape and size. I created the centroids and what I want to do now is to buffer those centroids with the exact same ...
0
votes
0answers
27 views

Unit of Geotools' getArea function

I have Polygons with WGS84/EPSG:4326 coordinates (like 13.57933804767844,52.5126298984133) and use the Polygon.getArea function to obtain the area of the polygon. But the result I get is something ...
4
votes
1answer
101 views

Comparing floor and roof areas using QGIS?

I am pretty new in this GIS topic and I would really appreciate if someone can help me with this problem. I am doing a research for university that shall show the available roof area for ...
2
votes
1answer
71 views

Area in KM from Polygon of coordinates

I have polygons from coordinates in (python shapely) that looks like this POLYGON ((24.8085317 46.8512821, 24.7986952 46.8574619, 24.8088238 46.8664741, 24.8155239 46.8576335, 24.8085317 46.8512821)) ...
8
votes
2answers
199 views

More accurate way to calculate area of rasters

In my daily work, I am constantly asked to calculate areas of global raster datasets in geographic projection at 30 arc second resolution. These datasets are normally the result of a Combine operation ...
4
votes
1answer
86 views

Routing ensuring all areas are touched

I'm making a web application with leaflet and OSM. It's all going well, but now I need a little help. I'm searching for a good routing engine, that's capable of creating the most probably taken route ...
0
votes
1answer
68 views

Converting area of a polygon from steradians to square kilometers using D3.js?

How can I find the area of a polygon in square km using D3.js? I'm not even really sure whether to use d3.geo.path.area or d3.geo.area. Here is my code (JSFiddle): var d = { "type":"Feature", ...
3
votes
1answer
83 views

Thiessen Polygon Total Area Calculations Model Builder/Python Code

I am attempting to create a tool using Model Builder (and Python code) for calculating the average annual precipitation of a study area using the Thiessen Polygon Method. My model runs good other than ...
1
vote
1answer
43 views

Is product purchaser in distribution area?

I am going to be using PostGIS 2 to create a lookup service. Given a point (lat/lon), I need to either find if a product can be distributed there, or b) a list of products or distributors. I am ...
3
votes
0answers
67 views

Why do each of my buffer-polygons have different areas

I`m using Qgis 2.2 and 2.4 and loaded a wms-map using the coordinate system ERTS89 UTM 32N. I set 8 points (all in on shp-fileand in UTM 32N) on various locations on the map. After that i created a ...
0
votes
1answer
82 views

Is it possible to have auto-updating area fields?

I'm using QGIS 2.4.0 and I've noticed some problems with the derived area and the $area field. Firstly, I have a polygon which is a filled ring, inside another polygon. The derived area, and therefore ...
0
votes
0answers
77 views

Dividing a polygon into certain areas (open source solution preferred)

I have a polygon with an area of 50.000m². Now i want to devide this area in two polygons of different areas with a line layer. The left polygon should have an area of 30.000m² and the right polygon ...
0
votes
1answer
37 views

largest area polygon

I have a layer of polygon shapes, I know this could be a quite easy question to answer but I am a beginner and probably I am not using the right concept or terminology when looking at the desktop help ...
0
votes
1answer
47 views

How do I measure the area difference between polygons in different shp files?

I have couple if shp files with 1000 polygons scattered in them (around 1k in each file) , each shp file represents a time frame (3 months period) and I want to show the a report with a progress of ...
-1
votes
1answer
49 views

creating circle with radius in metres

I am using shapely and python. How should I go about creating a circle using shapely whose radius is in meters? If i use sampleCircle = Point(1,1).buffer(1) print sampleCircle.area This returns an ...
3
votes
0answers
47 views

What is the area that OGR extracts from the (geometry) shp files for polygons?

The ESRI July 1998 technical documentation for polygon shapefiles at page 10 makes no mention of either area measures or length measures (apart from byte/record-layout matters). Yet OGR enables me to ...
2
votes
2answers
124 views

Python Add-in- Message Box to display area of selected polygons

I am looking to create a Python AddIn which calculates the area of selected polygons. I would like to be able to select the features, click a button on the toolbar, and a Message box displays the sum ...
2
votes
1answer
68 views

Prior art on rhumb line and great ellipse areas?

I'm adding the computation of the area betweeen a rhumb line or a great ellipse and the equator to GeographicLib. My formulations are briefly given in here and here. These formulations are similar ...
2
votes
1answer
126 views

Calculating area of polygon inside region?

I am new to geographic information systems and i need to calculate the area of a a polygon ( a circle to be precise) that falls inside the boundaries of a region, say a state or a country. For ...
3
votes
0answers
112 views

Calculating length of road network within a polygon [duplicate]

I have a road network stored in a gdb and some polygons in another gdb. I want to populate an attribute for each polygon with the total length (in km) of the road network that it overlaps. Any idea ...
1
vote
2answers
175 views

Calculate area inside polygons based on slope

I have some DEMs and have computed the slope in degrees for each one. I have also classified the slope raster into the following 5 classes: 0-3, 3-15, 15-35, 35-50, >50. What I want to do is to ...
1
vote
1answer
37 views

Looking for a complete list of cities by state, with area code

Our company is working on moving our sales assignments from area codes to ZIP codes, and we need some kind of dataset to help move existing assignments to the new system. Does anyone here know where ...
3
votes
1answer
99 views

Trouble calculating areas in QGIS using field calculator

I am testing various projections to calculate areas using ICES statistical shapefiles and the QGIS field calculator. I am using ICES areas downloadable from the following link: ...
1
vote
2answers
177 views

How to validate OpenLayers area calculation using PostGIS?

I am working on a GIS API that work on top of OpenLayers. I have a feature that calculates the area of a drawn polygon. I have tested it on the browser and the areas I got, appear to be correct. For ...
2
votes
3answers
81 views

Summarize the total area of land use polygons within map sheets - how?

I would imagine that at least some of you have encountered similar problems to mine and I´d like to hear how you solved them. I have a map sheet index (a grid as a shape file) covering a large area. ...
0
votes
0answers
33 views

Pros and Cons of a latitude adjustment grid vs other methods of area calculations

When working with high resolution global raster data in WGS 1984 I often need to calculate areas. Now the traditional way for me to achieve this has been to reproject the data to an equal area ...
2
votes
1answer
290 views

Calculating geometry area in ArcGIS for Desktop using ArcPy?

I have a polygon shapefile and I want to write a Python script to add a field named "area" and calculate its geometry areas. The script is like this: ...
2
votes
2answers
145 views

How to calculate area of shapefile with a merged layer

so i have 'save as''d the new project and layer with my new Custom CRS project string being '+proj=laea +lat_0=70 +lon_0=0 +x_0=0 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs'. ...
2
votes
3answers
135 views

How to figure out the unit of measurement from table fields?

I have a couple of fields with predefined values. In particular I have an 'area' field that I need to figure out its unit of measurement (e.g. km, miles, acres). What's the easiest way to do this?
1
vote
1answer
129 views

StArea() in sqlserver is in which unit?

I have a problem with saving STArea in sqlserver. Here is a query where I get the area of a polygon: select Geometry::STGeomFromText('POLYGON ((51.3386535086000000 31.7951253522000000, ...
4
votes
2answers
113 views

Wrong $area from field calculator (QGIS)

The area of the polygons in a layer, calculated by the field calculator with "$area" is wrong (much too big) for some polygons. If I draw the concerned polygon again, the area is calculated correctly. ...
3
votes
2answers
107 views

Create a buffer with a pre-defined area?

I have a road (line) system and need to create a polygon from it to show the right-of-way area. The right-of-way area is calculated in the field from taking measurements from the road centreline. From ...
2
votes
1answer
129 views

JTS “points must form a closed linestring”

I'm trying to create a polygon and calculate it's area using final GeometryFactory gf = new GeometryFactory(); final ArrayList<Coordinate> points = new ArrayList<Coordinate>(); ...
1
vote
1answer
28 views

Area of an EPSG 27700 polygon

I am working with EPSG 27700 polygon data in PHP. All the polygons are in the UK. The polygons do not have holes inside them. I'm hoping to be able to calculate the area of these polygons. For this I ...
2
votes
1answer
96 views

Problem measuring area with gps coordinates

I am trying to measure area from gps coordinates but fail to get the correct result (7200 square meters). I used the formula from this post but I get way too high number as result (should be in square ...
3
votes
2answers
173 views

Remove Holes Existing Within a Single Polygon for a specific area in Qgis

I have a shapefile that consists of a single polygon. I have gaps within the polygon that needs to be eliminated, but only the ones that are less than 200m2. I tried different ways but none of them ...
3
votes
3answers
79 views

Calculate the majority of one polygon in another (fishnet)

I am looking for a method to calculate the majority of one polygon file (a map of ecoregions) in a sampling grid (fishnet) in ArcGIS. The purpose is to assign each sampling grid (fishnet) to an ...
1
vote
1answer
150 views

How can I measure area in square kilometres from lat / lon gps coordinates?

I have code from openlayers that I cannot quite handle because I am so new for these kind of codes. My main goal is to measure area from n amount of lat/lon gps coordinates and convert the result into ...