topic Re: Automating point creation from bearings/distances in Data Management Questions

Automating point creation from bearings/distances

JacquelineHausle — Tue, 15 Oct 2019 02:06:29 GMT

I am trying to generate points for subplot plot centers based on an already existing point feature class. For each existing point, I need to create 3 points directly north and south at different distances. I found an online forum walking me through the process of manually creating points using the editor toolbar, but I am reluctant to use this method if I don't have to, so I figured I'd ask here first. Has anyone encountered batch processing point creation from this type of information? From each existing point, the bearings/distances will be the same so I imagine it would be a good thing to do using python, but I am just now learning the coding side of ArcMap and have no idea where to start with this.

Re: Automating point creation from bearings/distances

NeilAyres — Tue, 15 Oct 2019 09:45:49 GMT

dx = sin(ang) * distance

dy = cos(ang) * distance

angle measured from 0 due north and clockwise

See help on reading and writing geometries.

Re: Automating point creation from bearings/distances

RobertBorchert — Tue, 15 Oct 2019 12:17:16 GMT

Are all three distances the same for each direction and each point

Meaning North 100 meters, north 150 meters, and north 200 meters etc.

Just copy and paste the point features then use the move tool to move the needed distance.

Re: Automating point creation from bearings/distances

DanPatterson_Retired — Tue, 15 Oct 2019 12:35:41 GMT

If you already have the table with the X, Y , distance and bearing ….

and anticipating a potential question (how to connect them )

Bearing Distance To Line—Data Management toolbox | ArcGIS Desktop

allows you to produce a line connecting the "from" and new "to" points.

If you don't want the line, then convert the lines to points and you will be done

Feature Vertices To Points—Data Management toolbox | ArcGIS Desktop

Re: Automating point creation from bearings/distances

RobertBorchert — Tue, 15 Oct 2019 12:47:41 GMT

Building on Neil's answer it really comes down to simple math.

I have done something similar on several thousand features.

If the distances are consistent you can easily use my first suggestion.

If they are not and you know the distances.

Create an X,Y (double) and calculate geometry on them (Decimal Degrees)

I then export the table to Excel. It can be done in the database but I do it in excel.

You will need three new XY values for North and three for south

Determine what the distance is in Decimal Degrees

Assuming you have the distances in another row calculate what that distance is in Decimal Degrees

in the cell for the first Y north =Y1 + distance. X will stay the same.

You can then drag the calculation down all the way. I have done something similar when I had to generate spans between transmission towers and needed to calculate several thousand.

You can then use they XY to point tool