Questions tagged [density]
A density map depicts a number of objects per unit area.
174 questions
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Calculating intensity of a 0...1 scale
I'm trying to come up with the Intensity value for the Cells dataset (Diggle 1983). This dataset has coordinates from 0 to 1, probably percent, there is no actual unit to it as I think it was taken ...
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Mapping overlapping density estimates
I need a map that can represent density estimates. The estimates are tied to points, but are for 1 hectare (100m*100m) areas of which the point is the centre. Each point has at least one, but usually ...
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Percent coverage of a polygon in a raster grid
I have a wooded area polygon and a study area grid of cells with 300m resolution.
I would like to calculate a raster which shows the amount of each grid cell covered by the polygon. The density per ...
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Showing density of overlapping features via transparency in ArcMap?
Below is a famous map produced by the Facebook team, which shows the connections between their users. Where there are multiple overlapping features, the lines show more brightly, giving a clear ...
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Estimating population in flood zones?
I have a census tract shapefile with the population of a minority group and total population.
I am trying to analyze this group by high and low risk flood zones.
The problem is that not all of the ...
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Is Hot Spot analysis appropriate if you see hot spots in areas that you would expect to see them in?
I am working with vessel position data on ArcGIS 10.0. My customer has requested density analysis maps. I was curious if hot spot analysis would be a more appropriate analysis? The study area is along ...
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Arguments error when running LineDensity scripts in arcpy [closed]
I'm trying to use LineDensity tool on polyline features. The shapefile is small and includes some invalid geometries.
The code I use is an adaptation of an ArcGIS Help script.
Here is my code:
...
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Counting number of plants in area using images from UAV? [closed]
How do I count the number of pineapple plants in a 1-hectare block?
I have heard of these algorithms but I don't know how to do it.
I'm still a newbie of QGIS, ArcGIS and ENVI. I have the NIR, RGB, ...
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Where to find Population Density (shp. or grid) for Europe? [closed]
Does anybody know where to download shp. or grid file on European population density (inhabitants/ sq.km)?
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How to measure the compactness of a set of points
I'm looking for ideas on how to measure the compactness of a set of points. The idea is similar to identifying clusters, but instead I want to compare two distinct sets of points and return a measure ...
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Scale and density values in density map appear wrong when in projected coordinate system?
I'm making a series of maps illustrating different aspects (road density, location of dams, elevation etc...) of a single watershed in California. In most of my maps, I've had the projection set to ...
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Get all locations of Panoramio photos in a given extent
To create a visual quality heat map I'm trying to get a list of all Panoramio photos in an about 2000 Km2 wide study area. My idea is to perform a density analysis in GIS on a point shapefile ...
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How to reduce points by proximity
I got a layer with over 4 million points. The distance between the points are 1 meter.
How can i reduce the data so that no points have less than e.g. 10 meters between them?
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Displaying heatmap with large number of dense points of interest in QGIS?
I am currently trying to make heatmaps of bird observations in an area. I have had a lot of success making the actual heatmaps for most birds, except the ones that are extremely abundant. I use the ...
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find the population density of some points in qgis/postgis
I have the tiger census data of population density in each block group. I also have a different kind of data: traffic accident data, where an accident has a lat/lon pair. My goal is to find the ...
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ArcGIS dot density for small areas
I'd like to use dot density to display some data in Arc, but the areas (polygons) I'm displaying it for are so small in some cases that I suspect the pattern is being misrepresented.
If several ...
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Summing Raster cells to equal circles with specific sum using ArcMap? [closed]
I have application user density data that I've collected. Each gps point has a user density associated with it (for example: 150 users within a 1 km radius, which calculates to users/[pi*R-sq] OR 47....
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QGIS Grid Union Issues
I am trying to create a choropleth map of ice concentration over Lake Erie. I have data for all the lakes (I can clip it all at the end), which are in a point shapefile. I have laid a grid over the ...
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After turning census block data into a raster, how do I redistribute the density to reflect land cover types
I plan on rasterizing (terminology?) census block data relating to density to a regular 30 m by 30 m grid for use with NLCD data. I then hope to distribute the density of the original census block ...
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Low point density analysis
I'm working on a project for a conservation plan. Part of the plan requires that areas added for conservation have less than one structure per five acres (these are pretty large, mostly undeveloped ...
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How to make a density map from polygons/rasters (ArcGIS)
I would like to make a density map of grasslands. I have a vector layer of habitat classifications, I would like to a density map of grasslands within a specified radius. My thoughts are to:
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Kernel vs Point density [closed]
Can someone give me an example each where these two tools would be appropriate to use. I kind of understood what each of them does but can't seem to figure out examples where one would be more ...
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road density km/km2 calculation
I am trying to calculate the road density in my study landscape. I am using the spatial analyst, and the line density function. By default, the tool is setting a cell size of 3.6km*3.6km, and the ...
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Search Radius for Line Density [closed]
I have been working with GIS for many years but I am fairly new to the spatial analyst side of things. I am working with many satellite tracks for many different individual animals and would like to ...
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How to do dot density in ArcGIS Online?
I have some census tract polygons with language spoken at home attribute data behind them. I created them in ArcMap and produced a dot density map. However, after importing to AGOL it's only the ...
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Accessibility indication from points
I will simplify my question to be better understood. Let's suppose my study area is consisted by settlements A and B. They both have the same population (1000 people each). Each settlement was ...
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Interpolating species data from sample points in a small area [closed]
I have sample data from a small site (10 acres) which shows the number of occurrences of a particular species of snail over two sampling periods (fall and spring sampling). I want to try and ...
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Quality estimation of a spline interpolation with barriers
I interpolated the age of minerals for the Inner Tien Shan mountains (Kyrgyzstan) using the ArcGIS tool "spline with barriers". I use ~ 200 points for my interpolation. The barrier that I use is a ...
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Creating density map from point data in ArcGIS Desktop?
I have point data, where one point represents one 1 storm water outfall, looks like this:
(point data is across all of Long Island, New York).
I am having a bit of difficulty finding the best tool ...
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Density analysis producing extreme values?
I have point data of gas flares and I am trying to create a simple density raster of those flares. Results are either 0 or in the 100,000-1,000,000 range (when there's 5 to 40 or so points in each box)...
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Heat map / Density map from dynamic points table in MapServer (GeoServer)?
How can I create a heat map (some would call a density map) from a points layer in MapServer (or GeoServer)?
(preferably able to choose Interpolation method, NN, IDW, etc and color map with a ...
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How do I create zones using location features? [closed]
I have a list of rock art sites with a recording of every image within each site. For example, Site 1 has 4 kudu, 1 lion, 3 males and a locust; Site 2 has 2 leopards, 1 elephant and 3 giraffes; Site 3 ...
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Identifying clusters of points within a given distance
So I have a database of lats/longs representing incidents occurring on or near roadways.
My goal is to identify the street block areas with the highest number of incidents in the database. I don't ...
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Trying to Create a Global Choropleth Population Density Map then add Biodiversity Level
I am trying, quite unsuccessfully, to create a global choropleth population density map for a specific 120 countries, using ggplot2. Once I have created this choropleth map, I want to add number of ...
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Find area with highest relative density of one type of object
I'm using PostgreSQL/PostGIS and I have an advanced type of query.
My database contains two types of object - let's say pubs and churches :)
Is there a way that I can find the area with the densest ...
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Python problems with select by attributes and user input
I am attempting to create a tool where the user can input a census tract number within the city of Plano (there are 77 tracts) and it ultimately creates a map layout showing the population density. I ...
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Automating calculation of Population Density in Census Tracts?
I am quite new to Python and I am attempting to practice by making a simple program with ArcGIS. I wanted to make a script that automated the calculation of population density of selected census ...
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Calculating city density in GIS [closed]
There's a city called http://map.vmr.gov.ua/ in which each house has a type (for living, offices etc) and number of floors.
I want to find out city density - i.e. to assign certain amount of people ...
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Count the area of rasterdata in specific shapefile polygons (residential density in different districts)
I'd like to count the exact area of three different residential classes (low, medium, high) by district of a shapefile which contains 225 districts. like: district 1 has: XXX sqm low, XXX sqm medium, ...
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Creating contours with meaningful values from point data
I recently obtained a CSV containing the locations of all recorded bicycle accidents in Boston over the past few years. As an avid cyclist, I'd like to create a simple contour map that draws attention ...
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Making a population density map from tabulated (.txt) data in R?
I have California population density data from from the U.S. Census in an Excel file.
The spatial information is provided in ZIP Code Tabulation Areas (ZCTAs).
How do I plot a population density map ...
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How to fill in the parameters for kernel density estimation?
I am desperately trying to calculate animals home range with kernel. Unfortunately, the result is obviously incorrect and I cannot identify my mistake (I would like to post a screenshot but its not ...
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Creating Human Trafficking Heatmap in QGIS?
I'm trying to create a heatmap with about 325 points distributed around the city of Houston. (FYI Houston is a major human trafficking in the US: a title shared with LA and Atlanta depending upon ...
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how can i plot news stories to show how many stories include each country on a map of the world
We have a table that shows the number of news stories that include particular countries over a set period of time
there are three news channels that we have this data for and we would like to show/ ...
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Creating heat map or density map from stacked polygons in ArcMap?
I have a polygon shape file that has many overlapping features. Each feature represents an area used by polar bears. So some of the polygons overlap and some don't, and there are separate clusters of ...
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Summing up over area based on distance related function?
Through a field study, we learned that the density of a bird species in the forest was related to the distance to forest edge: ln(density) = 1.89*(distance to edge) + 0.34
Now, for any forest polygon,...
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Finding nodes with QGIS
As part of work in statistical mapping for school, I need to use QGIS to find the spatial extent of commercial nodes. A node is defined for this exercise as a zone of 75m in diameter where the ...
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How to Calculate Utilization Distribution Overlap Index (UDOI) in ArcGIS Desktop?
I was wondering if any of you happen to have any information on how to calculate the Utilization Distribution Overlap Index (UDOI) in ArcGIS 10? If I understand it correctly the UDOI takes two kernel ...
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Determine density or cover from a raster layer that has been clipped by a polygon
I am a very new GIS user using ArcMap 10. I have a raster layer of tree canopy that I have clipped so that the layer is in a polygon that is a circle with a 2km radius.
I have done this for four ...
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Producing density map in square kilometers using ArcMap
I have a shp file with the location (lat, lon) of lightning spatial distribution. I want to produce a density map of lightning occurrence per square KM. I used density point function and I don't know ...
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