Questions tagged [area]
Area is a quantity that expresses the extent of a two-dimensional surface or shape, or planar lamina, in the plane.
836 questions
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Getting Geodesic Area of GDAL polygon in C
I am using GDAL to create polygons for a GeoJSON:
OGRFeatureH hFeature = OGR_F_Create(OGR_L_GetLayerDefn(hOGRLayer));
OGRGeometryH hLinearRing = OGR_G_CreateGeometry(wkbLinearRing);
OGR_G_SetPoint_2D(...
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Aggregating the intersection area of multiple layers polygons in QGIS
I would like to calculate, with an aggregate, the area of multiple polygons overlapping another.
Let's say I'd like to know the area of my parcel (black dots line) covered by vegetation (green shapes)....
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How to deal with overlapping polygons in a categorized symbology
I am doing an update into a shapefile of Land Use and Vegetation, and, to speed up the process, I am just adding polygon over areas already with polygon to mark a new Use/Vegetation.
Although this ...
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Discrepancy in polygon area calculation in QGIS
I’m working with a polygon vector file in QGIS containing over 30,000 individual features. I want to calculate the cumulative area of all these polygons. I’ve tried two different methods.
Using QGIS:
...
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Size difference between raster and vector with GEE analysis
I'm using Google Earth Engine (GEE) to calculate burn severity from Sentinel-2 data. I also have polygons of burnt areas obtained from the EFFIS database. I use the polygon ın the GEE analysis to ...
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Tool "Rectangles, Ovals, Diamonds" produes smaller squares than anticipated in QGIS [duplicate]
I used the tool "Rectangles, Ovals, Diamonds" in a model to construct squares over points with the parameters:
buffer shape = 0 (rectangles)
width = 1000
height = 1000
rotation = 0
number ...
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3
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1
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Varying area values for the same shapefile in different QGIS Projects
I am getting different area values (not a big difference- 0.02 ha) for the same shapefile in QGIS. I have checked, and the shapefile CRS and project CRSare both the same.
See screenshots below:
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overpass turbo searching within a relation
I am trying to build a query that will search for amenities (like libraries for example) within a congressional district boundary relation in Openstreetmap (https://www.openstreetmap.org/relation/...
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Area correction factor maps for WGS84
Like an elevation map of the world, are there "AREA CORRECTION FACTOR" maps?
real_area(x,y) = sea_level_area * AREA_CORRECTION_FACTOR(x,y) (sea level is the WGS84 elipsoid)
The factor ...
- 2,572
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1
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Enforce a size constraint for polygons drawn in QGIS
When drawing polygons in QGIS, I'd like to ensure that they don't exceed a certain size (e.g. 4 ha). I could draw all polygons, calculate the area ($area) and then delete those that are too big, but ...
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Deleting small areas from polygon in QGIS
I want to delete small areas from my layer (Polygon).
Here there's a screenshot:
I already tried:
Delete holes (don't delete all of them)
Doing Multipart to Single-parts and then delete holes
...
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0
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Precise geodetic area calculation in hectares in EPSG:4326 using Python
I would like to calculate with Python the precise area (considering precision of 7 decimal places for coordinates) for area calculation for a MultPolygon layer using CRS EPSG:4326, without the need to ...
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Geodesic area of intersection of two polygons
Given two polygons on the WGS84 ellipsoid that intersect how can I get the polygon that defines their geodesic area of intersection?
Couple ideas I have considered
A Cartesian approximation using ...
- 320
2
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2
answers
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Removing small island from vector dataset with GeoPandas
I create an interactive map to evaluate aggregated values over specific administrative areas. When my tool is loading the initial map, all the countries in the world are displayed. I used the GADM ...
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Calculating area statistics for various categories with QGIS Expression
I'm working on a QGIS project and trying to calculate area statistics for various categories, but I'm having trouble getting the correct results using the Field Calculator.
Here's what I want to ...
