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Distance between points

Posted: Thu Feb 15, 2018 9:24 pm
by ilovecoffee1125
If I want to get average distance between points what tool would I use?

For example: I was planning to cut out a portion of my image and I want know exactly how many points are in that cut image and the average distance between the x,y,z points. How would I find this information?

Thank you,
CS

Re: Distance between points

Posted: Fri Feb 16, 2018 3:33 pm
by daniel
Well, to compute the average, you just need to call the 'Edit > Scalar fields > Compute Stat. Params' tool after having computed the distance. Choose the 'Gauss ' distribution, and you'll get the average distance, the standard deviation and the RMS (in the Console).

Otherwise I'm not sure what you mean by "the average distance between the x,y,z points", sorry :D

Re: Distance between points

Posted: Sat Feb 17, 2018 12:22 am
by ilovecoffee1125
Do you have to use M3C2 to get an estimation of distance between points or is there a simpler way to achieve this?

I want to know how many points the scanner was able to get on my target at different distances. In order to compare those values, I would need average distance between points.

Thank you,
CS

Re: Distance between points

Posted: Sat Feb 17, 2018 11:41 am
by daniel
You can use the much simpler 'Cloud to Cloud' distance. Depending on your data, it may also be more robust to fit a plane on one of the cloud and then compute the distances between the other cloud and the plane (with 'Cloud to Mesh' distance).

Re: Distance between points

Posted: Mon Feb 19, 2018 3:36 am
by ilovecoffee1125
Daniel,

Sorry to be dense, but I am not sure what you are suggesting. It is the same data I sent you a few weeks ago regarding M3C2 crashing when using the guess parameters option. If I cut my area of interest out, and want to know the number of points on that particular piece of the scan, can I highlight somehow and get a point count? Also, to find the average point distance for the selected area, is there a simple way to do so? Is the cloud to cloud distance an average?
Thank you for your help!
CS

Re: Distance between points

Posted: Tue Feb 20, 2018 5:23 pm
by daniel
Well, to determine the number of points in a cloud, you just have to highlight this cloud and look at the cloud properties (see the 'Points' entry).

To find the average distance, you have to compute distances (either with C2C or M3C2), and then compute the statistical distribution parameters (with 'Edit > Scalar fields > Compute Stat. params', and select the Gauss distribution).

Re: Distance between points

Posted: Tue Feb 20, 2018 8:14 pm
by ilovecoffee1125
Great! I just tested it out and it looks like it works well!
Thank you!