Questions tagged [area]
Area is a quantity that expresses the extent of a two-dimensional surface or shape, or planar lamina, in the plane.
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DB2 ST_AREA function with SRID: 4326 returns wrong units
On any other database system with a an SRID of 4326, ST_Area returns a value in meters. However, DB2 returns decimal degrees by default. I get that I can specify meters as an argument but why return ...
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Splitting polygon based on given proportion of its area in PostGIS [closed]
The problem I am trying to solve is to divide a given polygon into smaller polygons based on a given input number (proportion of the polygon).
In this example, the desired output would be a ...
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ArcGIS Pro: merge small polygons with their larger enclosing polygons
Polygons with an area size below a certain threshold should be merged with their enclosing polygons within the same layer. The image shows several cases in one example: in case of a threshold of 700, ...
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How ArcMap calculates area of polygon?
I am working on a project to compare between calculating the area of a polygon using Google Earth Pro and using ArcMap 10.8, and the methods used by the programs for that.
How does ArcMap 10.8 ...
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Calculation surface area for every cells [duplicate]
Surface area= Plan area /cosine (in Radian) slope.
I used cell plan area by multiplying cell size for example 12,5*12,5=156,25square meters
Surface Area = 156,25/cosine slope
result became surface ...
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Calculating area of GeoJSON features within Vector boundaries
I am attempting to calculate the area of total building footprints within each census block group within a state.
The building footprints are a .geojson file type and my census blockgroups are a ...
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How do I calculate the area of different land uses from one shapefile into a different set of polygons?
I'm using ArcMap10.8.2 and was trying to use Tabulate Area but I either didn't use it right or it is the wrong tool for the job.
I've attached an example image. I am trying to get the area of each ...
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Import error with using QGIS Native functions in Jupyter Notebook environment
I want to calculate area of all polygon features using Field Geometry function of QGIS 3.22 version. But somehow it always gives an import QGIS error, but when I tried to do a simple buffer of a ...
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Creating polygon with one third of world surface using R
I would like to create a polygon with (roughly) one third (or any other fraction) of the worlds surface.
I assume I should use an equal area projeciton like Lambert cylindrical equal-area, robinson or ...
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In GEE: Calculating area in WGS84 masking out regions with layers in different resolutions
I am trying to calculate the number of affected people by flooding, but only those who are living in urban areas. So essentially, I take the WorldPop dataset and overlay it with flood extent and land ...
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Calculate the area of a county bounded by a polygon in Google Earth Engine
As shown below, for the state of Texas, a portion of Bexar County is bounded by the given Polygon. I want to calculate the area of Bexar County contained within the Polygon.
Here's the code to draw ...
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Calculating the average of one field dependent on another in QGIS
I have a land use shapefile, which has a column:
labelled "LU_1", categorising different areas quite broadly (9 categories total, they are numbered 1-7, U and V).
There's also a field with ...
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Looping area calculations for multiple rasters in R
The following code works great on individual rasters and gives me the information that I want:
r<-rast("LuckSpring_2001.tif")
activeCat(r)<-"Class_name"
r
f <- freq(r)
f$...
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How to calculate the polyline area in QGIS
How to calculate the polyline area in QGIS?I have the width and length and I want to calculate the area of the river using that information so I can redraw my river using the area size calculated. ...
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Find the area of a raster created from drone data
I am trying to find the areas for a series of drone captured mosaic tiff data using ArcMap 10.8 which are irregular in shape. I have tried using Raster Calculator and multiplying by 0 to then use the ...
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Intersect Area service with points
I'm making a map viewer for my university final work but I have no clue of coding. I've been following the ESRI Dashboard tutorials and I've arrived to the code as I have it now.
I have two buttons, ...
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Land allocation to polygons with specific areas within a boundary
We are looking for a solution to create novel land allocations of an existing area into a subset of polygons for each allocation within the existing space.
A high level overview of the requirements ...
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Creating Multiple Instances of Measure Line
I'm trying to use multiple instances of the Measure Line and Area at the same time. More specifically, I need to measure setbacks from lot lines. The way Measure Line is set up, it becomes quite a ...
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QGIS area calculation disparity in identify feature vs PyQGIS
I have a single polygon layer in two different CRSs. I noticed the area calculations are way off between the two CRSs. EPSG 2284 and 5070
I have attached both layers. https://file.io/LRW3NniQU4ji
The ...
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Extracting area of the clusters of specific coordinates
I am working in GEE and I am trying to extract areas of clusters for some specific coordinates.
I have a clustered map of the area of all the clusters (using object-based clustering) and a list of ...
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Mergin Maps measure function available
Project works find. I use Mergin Maps on Windows 11.
But I need an essential function: Measure area and lines
Is there no function for that?
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Difference in calculating areas between Apache Sedona and GeoPandas
I am currently working on a project that involves calculating the area of a circumference with a radius of 0.001 degrees -created via buffer-, centered at latitude -4 and longitude -63. The resulting ...
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Polygon on scratch or shapefile area returns null in QGIS & EPSG3857
Just got started with QGIS (the software) today and I'm getting Null for a hand-drawn polygon, even for a circle shape. Here is what I've done:
Installed QuickMapServices plugin
Installed GeoCoding ...
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Polygons area calculation in one shapefile with different zones (ArcMap or Google Earth Pro)
My country is extended to 4 zones so for calculating area I must set data frame properties in ArcMap (projected coordinate system). I have one shapefile with many polygons (about 300 polygons). I add ...
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Calculate overall area of physically discrete raster areas in QGIS
I need to get the overall area of physically discrete areas of a raster layer up to a given cell count in QGIS. The following approach is what I've tried so far, but it seems a bit too complicated and ...
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Area calculation of classified raster layer
I am working with QGIS 3.22.4 and want to analyse the output of MaxEnt. Therefore, I have a raster layer showing the habitat suitability for my species in the whole oceans as .asc-data type. I have ...
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Calculate the average "radius" of a polygon in ArcGIS Pro
I am trying to calculate the average radius of RF coverage propagations. Each propagation looks almost like a paint splatter for visual reference.
I want to calculate the average radius across all of ...
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170
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Correct CRS for determining the area of my polygon in QGIS
I need to get an area of a polygon. The polygon when in GDA 2020 (7844) and GDA 2020 / MGA Zone 50 (7850) lead to significantly (20 hectares) different areas. The method for getting the area I am ...
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Adaptive polygon division in QGIS
Let say I have an irregular polygon layer that I want to divide into squares of fixed size (i.e. 50 x 50m). The simplest solution is to create a grid based on the polygon extension and then use the ...
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QGIS Delete holes "Remove holes with an area less than" is not working
In QGIS, both Windows 7 and Ubuntu, older and latest versions, I have used r.to.vect to create a GPKG polygon layer. When I try to delete holes below a certain value, all the holes are deleted, even ...
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QGIS: Calculating the area of category overlay between 2 shapefiles
I have 2 shapefiles (A & B). The polygons in layer "B" are categorized into 8 categories (1-8) and I want to add 8 columns in layer "A" with the areal distribution of the ...
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Detecting Land Use Land Cover Changes from Copernicus Corine Maps in GEE - Calculating Areas of LULC Change Pairs
I'm trying to detect land use land cover (LULC) changes between 1990 and 2000 using the Copernicus Corine land cover maps in Google Earth Engine (GEE). However, I'm unable to find change maps in the ...
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Calculating slope-adjusted surface area from DSM
Is there a (simple) way to calculate the surface area from a regular DSM raster considering the slope/aspect? In my case I've got a DSM (0.5m resolution) with a building, I would like to calculate the ...
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Deleting parts of MultiPolygon based on area using PyQGIS
I have a layer with MultiPolygons. Some of them have parts less than five m2 which I want to delete.
The QgsGeometry class has methods: parts() and deletePart(self, partNum: int). On parts() I can ...
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How to get correct area in QGIS in local coordinate system?
I vectorized a small area (75,000 square meters in reality) in QGIS in the local coordinate system.
+proj=tmerc +lat_0=0 +lon_0=38.48333333333 +k=1 +x_0=1250000 +y_0=-5712900.566 +ellps=krass +towgs84=...
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Calculating Area of each Classes by Region in GEE?
How could I calculate the area for each class of GHSL built-up layer for each district? I have tried the following code, but it doesn't work, and I don't know why.
Here is my code:
var countries = ee....
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Calculating equal area latitudinal bins
I want to generate a simple function for producing equal-area latitudinal bins based on a desired number of bins. I've come up with a bit of a dirty solution which seems computationally expensive and ...
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QGIS Plugin "Area Weighted Average" 0 is not in range
I'm a beginner in QGIS and I'm trying to calculate the population density. I have two layers, one layer with population attributes and one grid layer where my population data should be weighted and ...
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PostGIS concatenating tables with different SRIDs side-effects for area
I am quite new to Postgres/PostGIS and have an open question regarding 'mixing' tables with different SRIDs.
I know this is generally not recommended, but in my case, I will already be required to ...
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Global surface water/ How to compare area of latest image to older images and generate histogram
Based on the Global surface water script, I would like to compare the water decreasing per year and plot a histogram for the area lost per year. I know that there is a dataset that goes by monthly ...
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Identify largest class in area
I have a layer of polygons with different land uses, and another layer of polygons with administrative areas. I'm trying to find a way to determine which land use is dominant (in terms of area) in ...
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Calculating areal distribution of soil types within catchment layer in QGIS
I have two polygons:
Layer with +100 river catchments
Soil type layer (8 different soil types)
I want to calculate the areal distribution of soil types within each river catchment. Areas should ...
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Measuring study area of elevational ranges in raster file in QGIS
I have a DEM layer with elevation ranges of -413-5593 m, just as seen below.
Then I determined the altitude between 4100 and 5400 m using symbology and band rendering, got the map below and the ...
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AttributeError when calculating area in hectares in PyQGIS
I want to calculate the area of the polygon and add it to the attribute table as another column. I used this script:
from qgis import processing
inlayDir = iface.activeLayer()
P3_boundary = r'C:\...
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Divide areas from two vector layers
I'm using QGIS, and I have two vector layers (with polygons),
I'd like to get the % of area of polygon in layer b respect to polygon in layer A, and for that I want to calculate the area of a layer A ...
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Calculate poygon area in km2 from degrees to km2 in R
I found this but I think it is possible.
I am trying to calculate the area in Km2 of a polygon given by the vertices in degrees:
library(pracma)
x= c(-40.03953, -44.24278, -40.90583, -35.55361) #those ...
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Using raster cell area in a calculation using Python [closed]
I have a large raster full of integer values (1-20) and want to calculate the total area of cells of each value using Python. The raster spans a wide range of latitudes and so the area of each cell is ...
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Compute the area of differents buildings for differents regions in GeoPandas
I'm really new to GeoPandas so this question may have already been answered (I hope not).
I have a GeoPandas dataset with points that represent the coordinates of buildings and I would like to ...
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73
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Add polygon areas by roof orientation condition
I have a shapefile with building poligons and a raster file with the roof orientation (0-360º). I would like to assign the orientation to the building shapefile using QGIS. I converted the raster file ...
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Calculating the area of an intersection in PostGIS
I've got two tables in a PostgreSQL/PostGIS database, blue and purple, both holding polygons:
Now I need to calculate the overlapping area, for each polygon of the blue grid with only one of the ...
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