Within ArcMap, I have a point dataset representing accident data, and a road dataset. My goal is to attribute the road dataset with a count of how many particular accidents occured on each road segment. I can't however figure out how to produce a count of point/line intersections. I have tried a spatial join using 'one to many', however this doesn't produce a count, just multiple lines for a road with more than one accident. I've also tried a intersect, however ArcMap has told me this is not possible.
[GIS] How to produce a ‘count’ of points intersecting lines
arcgis-desktopintersectionlinepointspatial-join
Related Solutions
I've face a similar problem and created a programmatic tool that would:
Shorten my street centerline. Here I would take it from .4 to .6 for example (in this case I would consider only the dashes)
Street
==========
After shortening
====--====
I would buffer it for a small ammout, let's say 10% of the original street lenght. Imagine that you are buffering only the dashes in the schematic "drawing above".
Try to intersect it with pipes.
You can repeat 2 and three until you've found a certain number of pipes. The idea for shortening the center line is to eliminate the cases where you other perpendicular lines that you do not want.
Check a less ugly scheme:
Another approach is to just buffer, intersect and compare the angles. You can safely set a threshold of what "parallel" is. You will never have straight and parallel lines in this cases (some will be parallel, but that depends on digitizing). You take only the pipes that have similar angles to your centerline.
I have resolved the issue so I thoughht i'd close this by sharing the answer.
1) the "null" values on all rows but the first one
Thanks to Richard Fairhurst in the commenting section on the Patch tip. The patch fixed it.
2) returning the count value of points per line segment in my model, I had to:
use the 'Repeat Victimsation (Geographical) tool from the ESRI UK Crime Analyst extension: To count the number of stacked point at one location. This created a new layer with summarized features with a count value for each geographic location.
Use the Spatial join with the following criteria:
- Target feature is my Line feature
- Join Features is my RTC
- join operation is Join_one_to_many
- Left the 'Keep All target features' ticked off
- Right click on my Count value (from Previous layer) and use the merge rule to 'SUM'
- Choose Intersect
- Search radius of 10 m
And it seems to work ok (touch wood)
Thanks a lot.
Best Answer
Right click your road file, joins and relates > join.
Select join data from another layer based on spatial location in the first dropdown box.
Choose your point layer in the second dropdown box as the layer to join to the line layer.
Select "each line will be given a summary of the numeric attributes of the points that are" then select "intersected by it" below that.
Your new shapefile will have a "count" field added to it representing how many points intersect that line.