Point Distance Analysis

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10-31-2011 10:05 AM
MeredithLaBeau
New Contributor
I am trying to run a distance analysis on point features to centroids based on a certain class of land area. More specifically, I have all the urban rasters configured to centroid points. Then with another layer of points that are places I would like to analysis the influence of urban area on each of these points, which urban land contributes to each due to the distance, with an obvious cutoff of no more that 15 miles. When I run the point distance analysis it continually fails with a 99999 error. Not sure how to proceed to actually use this tool, does anyone have any suggestions, I would appreciate some advice!
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20 Replies
DanLee
by Esri Regular Contributor
Esri Regular Contributor
Could you post the two point datasets (urban centroids and places) for us to have a look?
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NobbirAhmed
Esri Regular Contributor
The Point Distance tool will return distances from each centroid to each of the places within your search radius of 15 miles. If you, for example, have 10 places within 15 miles of centroid 1 then you'll get 15 rows in the output table for that centroid. You'll get kind of a distance matrix but arranged in rows. The Distance field in the output table will show the distance between a centroid and a place. Have you run the tool this way?

Which version of ArcGIS you are using?
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MeredithLaBeau
New Contributor
I am using ArcMap 10 to run this analysis, but you can only run within 15 miles? Is there a number of points you can run the distance too. I am running over 100,000 urban centroids but obviously most are not within 15 miles of the point A, but may be located near point G and so on? I can try to post the datasets.
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MeredithLaBeau
New Contributor
urbans centroids(to large to upload) & pcs points (uppermi_pcs.zip)
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NobbirAhmed
Esri Regular Contributor
... but you can only run within 15 miles?


I used 15 miles as an example (got it from your first post). If you leave out the search radius (blank) then distances to all places will be calculated.

Is there a number of points you can run the distance too?


Use Generate Near Table tool. Uncheck Find only closest feature and enter the number in the Maximum number of closest matches parameter.
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DanLee
by Esri Regular Contributor
Esri Regular Contributor
It seesm you are analyzing 26 points (places in your zip file) against 100,000 urban centroid points. Are these two data in the same coordinate system or projection?

Without the centroid data, we can't reproduce/investigate the problem. You can try this workaround:
1. Run Buffer tool with 15 miles distance and the ALL option for Dissolve Type. You should get one multipart polygon.
2. Run Clip tool to clip the centroid points by the buffer polygon.
3. Run Point Distance or Generate Near tool using the places and the clipped centroid points.

Hope you can run through these successfully.
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MeredithLaBeau
New Contributor
Just a question on the generate a near table...Alright for that particular state I have only 26, but others have 100 or so point with one million or so urban centroids.  Although not all will be within the radius, as we are at state level. These are both in the same coordinate system. So I clipped the centroids to the ones only within a 10mile buffer of each pcs_point, then I used the tool generate a near table, giving me an output. Some buffers overlay each other due to proximity within a 10mile radius, but when I enter the generate near table, I get one unique value for each centroid. Does this tool only select the nearest centroid to that pcs_point for each centroid?
Thanks
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NobbirAhmed
Esri Regular Contributor
Does this tool only select the nearest centroid to that pcs_point for each centroid?


How have you set your Find only closest feature parameter? Make sure it is unchecked. Then enter a number for the last parameter Maximum number of closest matches - enter maximum of the numbers, such as, enter 105 from 26, 100, 105.
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MeredithLaBeau
New Contributor
can you clarify that, i have the box unchecked, but why enter only a small number like 105 for 26? I am a bit confused. Thanks for all the help
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