Geometry... Stuff to do with points

Blog Post created by Dan_Patterson Champion on Feb 28, 2018

Geometry  Perhaps its due is overlooked. 

A pictoral of some of the things you can do with a set of points with a basic license in ArcMap and PRO with a bit of python and a toolbox to house the scripts in.


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Begin with some points

Random they are, no order.

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Put order to the setA radial sort was performed so that the mess was ordered by their angle relative to the x-axis.

Lines were drawn to the center of the cloud (just because)


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What do we have now

Since the points are ordered, connect the dots.

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Lets look at things conventionallyEveryone loves a convex hull.  It encompasses the points as a group.  There are other containers.


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But some of the points are far from the centerA quick little negative buffer to only keep the points within 90% of the average distance to the center.


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Convexity.... A different view on the data

Switching the selection in the above, then connecting the dots gives us a convex-ish hull..

Hmmm I wonder if you can change the rules to get a different view?



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Every cool map has textureFill in boundary, obliterate the dots and 'forest' fill.  Just because we can



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Connecting each point to its closest


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Connections to 3 closest

Starting to see groupings and spaces.


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Trees are useful (MST)


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Make patterns from a single point (Ulam spiral)

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Archimedes only needed a single point


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