Issues with NEAR and Point distance

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05-14-2020 12:33 AM
SamanthaDe_Simone
New Contributor

Good morning, 

I am a researcher focused on the use of point cloud data generated through SfM-MVS photogrammetry. For my latest analyses I would like to use the near/point distance tools for checkpoints analyses of my point cloud. 

I had some issues that are summed below and I was wondering if you had any suggestions on how to overcome them.

-Issues in uploading my point clouds: they are quite large files. One is generated through photogrammetry in a national grid coordinate system (OSGB36) and the other from a laser scanner. I had to import them in Cloud compare first to align the laser scanner and photogrammetry one. If I save them in .txt ArcMap (I'm using a 10.3 v) display only two points. As shape files .shp it says it can project them. So I sampled a region of my point cloud and saved them as csv ( so i could edit edits etc). Nevertheless i will need to upload the entire thing if possible so any suggestion is really appreciated! 

-Generating a Near or Point distance table: if i use the "Generate Near Table" command the table gets generated fine and the different fields populated. The issues arise when I try to use the normal Near and Point distance tool. I know the syntax needs to be specific so I saved the file with the appropriate fields. When I use near it gives me the following warning: Output feature class empty. When i use the point distance it simply generates a table with nothing populated. 

What I need to put as IN_FID are five points (taken with a total station), with my point clouds as NEAR. I wondered if the fact that i had so many points in the NEAR compared to the IN_FID could be the issue but even when I have one point cloud (laser scanner) as near and the other as NEAR (photogrammetry) I get the same issues. 

I attach a PDF with some screenshot that I hope will help to support my points.

Many thanks in advance to any suggestion!

Samantha 

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