Finding points a certain distance from each other

Question

I would like to find the maximum amount of points within a specified domain that are a certain distance from each other. For example, how many points within an area are 1000ft from each other? I envision each point with a radius of the desired distance, but I don't know if I must start with a point or what.

Answer 1

It sounds to me that you would get an answer to your question by creating a subset of your points dataset and running Near analysis (if you're using ArcGIS) on it subset choosing it as both: near and input features. Description of that tool. Having done this you would be able to choose points that have a neighbor in the same dataset within certain distance.

Answer 2

Just from the sound of it, you want to pick a point and buffer it 1000ft, then give a total of how many points are within that buffer. Is that correct? If, so you just need to loop through each point and buffer it a 1000ft, then take the buffer and do a spatial query, could be a within or contains, to get the total count. I do not know if you are using ArcGIS, QGIS, etc., but basically that is the process.

1. Buffer point of interest
2. Use buffer geometry to perform a spatial query to get count of points within
   the geometry
3. Repeat until finished.

Answer 3

If you're interested in a Python implementation of what Jamie suggests, try running this code (adjust paths to data accordingly in lines 4,5,8,9,10):

note: untested Tested/Confirmed

import arcpy

# buffer points
arcpy.env.workspace = "C:/GIS/temp"
arcpy.Buffer_analysis("pointData.shp", "C:/GIS/temp/pointDataBuffer.shp", "1000 Feet", "#", "#", "NONE")

# spatial join and count the number of points falling inside of each buffer
target_features = "C:/GIS/temp/pointdataBuffer.shp"
join_features = "C:/GIS/temp/pointData.shp"
out_feature_class = "C:/GIS/temp/pointDataBufferJoin.shp"

arcpy.SpatialJoin_analysis(target_features, join_features, out_feature_class)

The join_count field which is created in your pointsDataBufferJoin file will tell you how many points matched up ("Intersected") with each 1000 foot buffer.