Questions tagged [aggregation]
To combine data into larger units. For example a group of points to a polygon, or political subdivisions (provinces) to larger entities (country).
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ArcGIS Pro: Aggregate Polygon using Aggregate Field not honoured
The aim
For cartographic purposes, certain features have to be generalized depending on the used scale. One step in this workflow is the aggregate polygons based on a category.
The problem
Using ...
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Expression works in one QGIS project, but not another
I have an expression in a Print Layout that populates a label with an attribute, based on which polygons are selected in map view. In the QGIS project that I made, it works perfectly. I tried copying ...
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Aggregate entities by single value distributed in two fields - QGIS
I have a polyline layer with unique value ("loop A"; "loop B", etc.) distributed between 2 fields just like this:
ID
Field 1
Field 2
1
Loop A
NULL
2
Loop A
Loop B
3
Loop C
Loop ...
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Cover area with point clusters bounds
Suppose, I have an area covered with regular grid points.
Points have some categorial attribute. I need to cover the area with polygons corresponding to the value of this attribute (it is like bounds ...
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Filling in attributes from a different layer in QGIS batch mode
I have a point layer with an X,Y field, containing the coordinates of each point separated by a comma.
I'm trying to batch process r.water.outlet based on these X,Y values from a different layer, the ...
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1
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Make the aggregation function in the form menu more versatile for different projects?
I have expressions for a table field that has a map layer named as a data source file (building_ex.shp). I plan to save this setting as a style and use it in other projects, but in other projects the ...
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Google Earth Engine: reduceRegion on multiple bands of daily aggregates
I found this hourly climate-dataset in the GEE catalog, which I want to utilize, to get the daily mean value for six different bands for the time between 2017 and 2022 based on one user-defined AOI (...
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2
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375
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QGIS Field Calculator - adding up value from another layer
I need to sum values from one layer over another, in a 1-n relationship, based on an attribute.
For example:
Layer 1, Column to join name_1, Number column to enter value number_1;
Layer 2, Column to ...
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Google Earth Engine update band values of aggregated image to just the values depicted in brackets in the band when data type is double
I am trying to aggregate the hansen forest loss data from a 30 x 30 m resoltuion to 1 km x 1 km resolution, where the value of the band is the proportion of the cell coverage. I feel like I am close ...
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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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Aggregating features values based on name attribute and geometry in QGIS
In QGIS 3.28.1 I have a map with many points (it does not contain polygons and lines), and there are some duplicate points on top of each other in the same geographic location, and I would like to ...
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How to aggregate data according to week and get centroid of all points from that week?
I have a dataframe that looks like this:
I want to extract data by aggregating the dates by week, and taking a sum of the observation counts like this:
pd.DataFrame(data.groupby([pd.Grouper(key='...
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Aggregate using one field and retain corresponding attribute from another field in QGIS
This is a follow up question to my previous question Clip polygons to retain only top polygon in areas of overlap using QGIS and its answer.
I have successfully aggregated my overlapping polygons to ...
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Aggregating values at building level data and getting values for block group level and by building type
I have data for the building level. I have classified these buildings into 5 different types. I need to aggregate the values of each building type and get data at the block group level.
How can I do ...
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3
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Aggregating attributes from line to point using QGIS Expression
I have two feature classes: point and line. The purpose is to make geometrical relations between them. For instance, if points are on line then they automatically take attributes from a specific field ...
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QGIS: intersect and filter in expression based filter
I am trying to filter as part of an intersection but can't work out where to add the filter.
The intersection works fine
intersects($geometry,aggregate('DSC_Roads','collect',$geometry))
But where can ...
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Aggregate (dissolve) polygons leaving internal lines - R
After dissolving polygons, some of the internal lines remain. It seem to be a problem common also to ther softwares (ArcGis and Qgis at least). The dissolve result is this:
To dissolve using R, I'm ...
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How to aggregate total amount of precipitation from all cells within three seperate catchments?
Using ArcGIS Pro, I ran 4 different IDW interpolations (rasters) of rainfall measurements across 26 measurement stations (point features). I'm trying to now aggregate the total amount of precipitation ...
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1
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55
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WMS filter/aggregator for GetCapabilities
I have a GUI that consumes WMS layers. We want to be able to connect to multiple WMS services, but we don't want the users seeing all the available layers, just the ones that are relevant for our use ...
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216
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Speeding up the process of aggregate function in QGIS
I'm conducting aggregate function in QGIS. But since the feature number is high, the process is very slow. Is there a way to speed up the calculation process?
By using this function: sum("lengths&...
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Aggregating child features with parent attribute values in QGIS
I found this question when looking for my answer Referring to the parent layer with aggregate functions in QGIS
I need to do something similar. In another words I need to join attributes by field ...
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Seeking PostGIS equivalent of Geopandas dissolve method
Suppose I have a multiline string feature that I have brought into PostgreSQL as a table called nld_table with the following columns: 'SystemID', 'SystemName', 'Location', 'Accred', 'NLD_Access', '...
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133
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PostGIS/PostgreSQL Heavy performance issues with SUM
Not sure if this is specific of GIS stuff or simply a SQL performance issue, but due to the nature of the issue and that I am working with H3 data types here it goes
I have a query that runs very ...
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251
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Unexpected resolutions when aggregating rasters with raster package in R
I have a (near) global raster of elevation data in WGS84 with a resolution of 0.00893153 x 0.00893153. I am trying to aggregate it to a resolution of 0.166667 x 0.166667 with the following:
fact = 0....
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228
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Resampling high resolution binary raster
I have a large, high resolution raster of binary data that I need to reproject and resample to align with a lower resolution dataset. Because the original data is binary, I need to aggregate using the ...
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1
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215
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Aggregating vector grid tiles to lower resolution in QGIS
I have a vector layer with grid tiles of 100x100 meters that contain data for each tile. I now would like to aggregate those tiles to a lower resolution (e.g. 200x200m, 1000x1000m), preferably in QGIS ...
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1
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105
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Polygons with same geometry and bbox but can't be aggregated with GROUP BY
I'm trying to create a constraint unique on a geometry column to avoid duplicate ones, following https://dba.stackexchange.com/questions/299098/why-doesnt-my-unique-constraint-trigger/299107#299107
...
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208
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Aggregate interpolated data at county level with R
The raw data is at the state level and I would like to go down to the county level. To do this, I first adjusted the data to county level and then interpolated it.
The raw data on state level looks ...
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151
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Geometry simplification for large scale aggregations in GEE
When aggregating on a large scale in GEE, does geometry simplification matter?
For example, when aggregating climate data on 30 km/pixel (e.g. NEX-GDDP), does it make computational sense to change ...
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450
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Aggregating features values based on distance in QGIS
In a polygon dataset, I try to summarize values of surrounding features based on a minimum distance if their area is too small (e.g. 500 square meters).
For example, I have 3 polygons with 300, 250 ...
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Aggregating data by zip code over time in QGIS
I have data that is at the zip code level and I am looking to be able to have that data aggregate over time with a temporal display of the map. Is there a way to do this using QGIS?
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810
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Get the sum of an attribute within a set radius for each row using GeoPandas
I have grid map that contains cells. Each cell is represented as a row in the dataframe, and each row contains the average population "pop" attribute.
What I need is that for each of these ...
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272
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Getting median value of attribute for duplicate polygons and dropping duplicates using GeoPandas
I have a DataFrame that resulted from spatially joining a digital elevation map with a square grid map.
This unexpectedly resulted in duplicate rows where two rows will have the same "geometry&...
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Merging zipcodes based on population to create larger areas in QGIS
In QGIS I have a shapefile with small geographic areas (zipcodes) with population in each zipcode area. Currently the population per zipcode vary very much, some as low as 1 person living in them. I ...
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446
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Merging touching polygons in same layer using ArcMap [duplicate]
I have a shapefile consisting of many polygons, and I would like to merge them when they touch each other (see red lines below).
I've been trying quite a few tools in ArcMap 10.7 such as Dissolve, ...
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1
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Why does aggregation of MODIS pixels not sum to 1?
I want to find the fractional cover of different tree species from MODIS (30 m resolution). I use R to stack, aggregate (1020 m resolution) and thereby find the fractional tree species cover for a ...
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229
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Aggregating and calculating fractional vegetation cover from raster using R
I have some MODIS data on vegetation cover. It is at a 250 m resolution and I would like to aggregate the pixels on a 1 km scale, and at the same time calculate the fractional vegetation cover since I ...
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2
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190
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Dissolving linestrings by uniqe value in field using QGIS
I want to dissolve a line geometry by a unique value in the field "RoutenIDs". For example dissolve line 37 to 43 with value 27. Dissolve line 37-46 ... with value 1999 and so on. Is there a ...
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Creating polygon which outlines many smaller polygons to show their extent using ArcMap
I am looking at a wildfire, and I need to display the wildfire footprint, however all I have is a raster of classes, I converted that raster to a polygon for values that show low to high burn severity,...
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54
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Customizing factor in aggregate tool in ArcMap
I have a raster of 30m cell size, with either value 0 or 1.
I try to aggregate this into a 1000m cell size. I can then see the proportion of '1's, in a 1000m cell size raster.
But the Aggregate tool ...
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Aggregating MultiPoints to MultiPoint output using ST_Collect
I have a geometry column that stores MultiPoints. How can I aggregate MultiPoints having another MultiPoint as a result, not a GeometryCollection?
select st_collect(geom), id
from my_table
group by id
...
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How to group polygons based on spatial proximity and field value?
I have a shapefile consisting of the day of the year on which the temperature in a lake exceeds 15 degrees Celsius. I can see clear patterns in this (here seen as a raster):
I want to group the ...
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Aggregate polylines in JavaScript (Leaflet)
After executing a certain amount of routing calculations, I have a list of vehicle routes as shown in the image below. Now I have added an opacity to these lines to visualize the frequency of certain ...
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GeoPandas TypeError: geometries are not orderable (numpy: TypeError: '<' not supported between instances of 'Point' and 'Point')
I'm trying to group rows of a GeoDataFrame based on a common gid value and aggregating two columns for which the values differ but I am facing this error:
TypeError ...
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84
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PostGIS: Aggregate small raster to larger raster
I am just getting into rasters in PostGIS and I have stumbled across a problem I can't solve:
Given one large raster A (e.g. pixel size 5km x 5km) and one smaller raster B (e.g. 1km x 1km) which might ...
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481
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Sum/aggregation of polygon's values within other polygons using dyplr
Let's say you have two sf objects made of polygons. In my case, one is administrative units (ADM) and the other is buildings (SHAPES). I would like to calculate the sum of the surface area of SHAPES ...
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ArcGIS - Percentage in Census tract to HUC
I’m trying to figure out the percentile of demographic value (minority %, poverty %, etc.) per watershed at HUC12 level. I was hoping that I can somehow convert the values from census tracts into HUCs....
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In QGIS my expression aggregation in attribute forms slow works
There are two layers: Parcels and Parking.
Parking has attribute: parcels_objects, this is lists of parcels intersect of parking.
When I create a parking object, I want to calculate all parcels ...
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ArcGIS Pro - Clip (Modify Features) aggregates nearby geometry
I have a large polygon that contains several several other (smaller) polygons. Some of these smaller polygons also intersect with each other but they all at least 'touch' the larger polygon.
I want to ...
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2
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Aggregating point data into polygons using QGIS
I would like to aggregate point statistics to a specific polygon layer which is a 100*100m raster.
The point dataset includes address data of buildings and their heating energy consumption. So the ...
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