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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Calculating area of intersection of two segmented polygons in QGIS
I have two sets of polygons. One contains villages, the other farming areas.
There can be several farming areas in one village. Crucially, there can be cross-village farming areas.
My approach to get ...
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GEE outputs different number of groups for each year when performing grouped area calculation in GEE
I wrote a function that aims to calculate the pixel area of each of 19 land cover classes within a masked image's area (MODIS burned area). I mapped the function over 20 years of land cover and burn ...
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Rough conversion in SQL for decimal degrees to square meters/meters
I'm dealing with a database (Teradata) that doesn't have any support for anything other than decimals/decimal degrees. As a result I can't use any of:
ST_Area (can't get area in square meters)
...
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Overlapping 2 raster data
I have a raster file which a vegetation indices file where a certain indices value say: 0.2-0.4 is represented in Green Color and rest in white as shown:
I now want to overlap slope for my study area ...
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Is there a way to get square meters from a Teradata ST_Area call?
I can't seem to find a spatial reference system in Teradata that returns square meters from a call to ST_Area(). I've tried 1619, which seems to be the Teradata mapping to 4326, it returns square ...
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R: 'area' function for las-file [closed]
I want to work on this project: https://gitlab.gwdg.de/tanja.kempen/skidtrail-detection/-/blob/main/README.md?ref_type=heads where I'm using the SkidTrail_Preprocessing.R R-Script.
Software: RStudio ...
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QGIS 3.34 Calculate area in curved geometries
I want to calculate the cartesian area of a curved geometry, a circle, with a radius of 2500 m.
First, I buffered a point with 2500 m radius and used the function "Convert to curved geometries&...
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Getting the right surface area raster layer
I am calculating the surface area of a raster file and even though I have tried to put it in all sorts of projections it still shows dg2. I have now used the projection equal earth greenwhich which ...
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Unexpected output from masked area calculation in Google Earth Engine
Using a 500m MODIS burned area dataset in GEE, I want to find the area burned in a period of time (say, a few months). Specifically, I want to find the area of pixels that have burned one or more ...
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Calculating Area of Parcel/ Building Footprint
I am trying to calculate:
Total Parcel Area (Square feet)
Sum of the area (sq. ft.) for all the buildings on the parcel (building footprint of all structures including garages, clubhouse, common use ...
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Calculate ratio of 2 polygons using QGIS modeler
Working with QGIS modeler, I need to do some arithmetic operations with some polygon areas.
Let's say there are 2 polygons in layer A and layer B. And I'm inputting them into the model using Vector ...
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Calculating Area of 2D Shape in 3D space
With ArcGIS Pro, I want to calculate the area of a roof. I have LoD2 building data and have only exported the roofs. These roofs have a 2D shape but are situated in a 3D space. When I calculate the ...
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Measure area of a polygon on OpenStreetMap
How can we measure the area of a polygon on a OpenStreetMap map?
It can be either:
the area of a hand-drawn polygon,
the surface area (at ground level) of an existing building
It seems the standard ...
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Creating rings with buffer as polygon in QGIS [duplicate]
I need to draw circles with a buffer in one view. It will be an area around cities. I think it can be solved with a buffer or a cutout from the circle.
How can I do this?
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Find area of patch if two vector files overlap
I have two vector files containing polygons. I want to calculate the area of polygons in add if they are touched by polygons in re. I have tried but I only find the area of the intersected area, but I ...
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Real Time Area calculation while drawing polygon in ArcMap
How can I visualise real-time area while drawing a polygon in ArcMap 10.8?
I mean, when we draw a polygon in Google Earth Pro, it shows real-time area with each drawing vertex.
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Tool or plugin in QGIS that allows seeing measurements/area of polygon/line while drawing it
I am looking for either a tool or plugin in QGIS that allows me to view measurements and/or area while creating a ploygon/line. I know I can measure it afterwards, but I am specifically looking for a ...
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Different area values for same polygon in ArcGIS Pro 3.2.2 vs QGIS 3.28.4
When I calculate the area of a polygon in QGIS using the area($geometry) function in the field calculator (and also when using the "add geometry attributes" function in the processing ...
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Calculating group area percentages in ArcGIS Pro using Summarize Within
I have a grid (vector file) in ArcGIS Pro, and I want to calculate the percentages of the area of different anthrome types in another vector file (Anthromes 12K DGG Dataverse) for each grid cell. I ...
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Absurdly large area estimates when extracting landcover area for individual polygons (CORINE Data)
I want to extract area under different CORINE classes as a part of my master's thesis. I am facing problems with the area estimates that QGIS calculates for landcover classes from the CORINE dataset ...
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QGIS ellipsoidal area values changing very slightly between calculations while planimetric values stay the same
I have a number of vector shapefiles that I need to calculate the geodesic/ellipsoidal area for. These shapefiles are accessed and updated regularly, with the area recalculated each time they are ...
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How to calculate the area of each grid cell of a raster in Python?
I have a square raster of size, let's say, 100x100 cells, with each cell being 200m X 200m. This raster is not in an equal-area projection, but is centered on the North Pole, meaning the actual area ...
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QGIS Count values between two numbers inside a polygon in another layer
I have 2 layers.
LayerA are multiple polygons of the area that i'm evaluating (Red boundarys).
LayerB is a MSAVI raster to vector with the data (multicolor greens - blues).
I want to calculate the ...
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Calculating information for selected parts of the polygon with PyQGIS
I have a polygon that is formed using Quick OSM.
After that, I add an area calculation field to it, automatically using the QGIS tools.
How can I use PyQGIS to get the sum of the areas of the ...
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Finding the name and area of layer under buffers
I am new to QGIS and am using version 3.34.2 (Prizren). I am using two files to accomplish a couple of tasks (explained below). The first file shows the outline of groups of villages (gram panchayat [...
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How can Cartesian and ellipsoidal perimeters and areas be so different in an EPSG:3857 layer?
For a particular polygon of mine in a "EPSG:3857 - WGS 84 / Pseudo-Mercator" layer, the derived measurements QGIS reports are:
Ellipsoidal perimeter: 1015 m
Cartesian perimeter: 1218 m
...
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How to find an Area of Interest in ERDAS and is there a way to make them stand out?
One of the things I've been doing is creating AOIs (Areas of Interest). They were supposed to be at least 30 pixels in size. However, I have lost track of one of them which was classed as "...
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Intersection in geopandas takes long time to execute
I got two dataframes in GeoPandas Python. One table contains around 2.2 million rows of data (geometry type is Multipolygon) and other table contains around 3800 rows (geometry type is Multiplygon). I ...
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Buffer: shape_Area=0
I used the GPX to feature tool to add data points to my map. I draw buffers with a different radius around each point >10 m (some of them overlap). However, the column shape_Area is 0 for all the ...
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Determine area enclosed by multiple segments
I am trying to determine the area enclosed by multiple linestrings. For example, in the following picture, I have 4 linestrings, forming 2 closed polygons. I'd like to be able to get the coordinates ...
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Why is my code for flood pixel area calculation timing out?
I have made a flood map of Bangladesh following a tutorial. I am trying to determine the flood-affected land area by calculating pixel area. The map is displayed fine and the code for total area ...
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393
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Calculate area under each class for a feature in a shapefile
I have a shapefile that you see in attached picture and you can see it has eight classes for a feature shown in picture. How do I calculate area under each class. I would like to export area ...
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Rasters not having the same total area for classes within the same study area
I have multiple rasters for various data: LULC, Elevation classes, Slope steepnees classes, Soil types.
All those rasters have the same properties: all have the same number of columns and rows; same ...
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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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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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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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Creating Multiple Instances of Measure Line [closed]
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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345
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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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