topic Re: Create Pseudo Drilling Spacing Units - Polygon inside another polygon from its boundaries in Mapping Questions

Create Pseudo Drilling Spacing Units - Polygon inside another polygon from its boundaries

coleblair — Tue, 05 Dec 2017 20:06:34 GMT

I am trying to create pseudo Drilling Spacing Units. That corresponded with the section, township and range that they are generated from.

I am working with Sections from the Land grid in Oklahoma; Section Township and Range.

I need to generate a new polygon inside each section, with specific distances from the section boundary that it is generated inside of. The new polygon needs to be parallel with the boundary line and 165' from the north line, 165' from the south line, 330' from the west line and 330' from the east line.

This is ruffly what one new DSU (Drilling Spacing Unit) would look like

This is a schematic for what dimensions and the boundaries that are generated from.

The finished product would auto-generate the polygons like so???

I have used the buffer tool to create a polygon from the midpoint, however the boundary's that the new polygon draws from will change as you move across townships / ranges. so i need to go off each sections unique boundary.

I have been reading and searching so i apologize if this has been covered. however i have not found anything yet. I would appreciate your help, thanks.

Re: Create Pseudo Drilling Spacing Units - Polygon inside another polygon from its boundaries

DanPatterson_Retired — Sat, 11 Dec 2021 16:00:37 GMT

Generate a shape from a 'centre' and a displacement, then move the centre sequentially in the X and Y direction generating the bounding box coordinates as you go... here is a simple workflow explicitly shown for detail

Xc, Yc = 10, 10   # center coordinate

dx, dy = 4, 3.5   # delta x, delta y

L, B = (Xc - dx, Yc - dy)   # ---- get the left and bottom coordinate

R, T = (Xc + dx, Yc + dy)   # ---- get the right and top coordinate

LB = (L, B)  # ---- generate the 'box' coordinates

LT = (L, T)

RT = (R, T)

RB = (R, B)

LB, LT, RT, RB

((6, 6.5), (6, 13.5), (14, 13.5), (14, 6.5))

# --- to form a polygon, add LB to the end of the list
# --- now 'move the centre by the centre spacing you need and regenerate‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

Re: Create Pseudo Drilling Spacing Units - Polygon inside another polygon from its boundaries

coleblair — Wed, 06 Dec 2017 14:53:53 GMT

Dan could you clarify
- Is this just a workflow, i don't understand if you are suggesting if i just use toolbox tools, a script or the model builder?

Thanks

Re: Create Pseudo Drilling Spacing Units - Polygon inside another polygon from its boundaries

DanPatterson_Retired — Wed, 06 Dec 2017 15:05:11 GMT

Oh sorry... It was a generic workflow for a script. It would have been dead easy if your offsets from the outer polygon were equal since it would have just been a negative buffer. I figured by the time you would have had to fiddle getting the differential offsets, it would have just been quicker to generate a rectangle that fit within the polygon, then replicate it in all the others.

Re: Create Pseudo Drilling Spacing Units - Polygon inside another polygon from its boundaries

coleblair — Wed, 06 Dec 2017 16:09:00 GMT

Ok i believe i understand now. I get the workflow of the script, but i have never attempted to script anything.

- If i have a end of the year deadline do you think it would be easy to figure out or maybe just do something with model builder? I realize this is very broad and opinion based question.

Re: Create Pseudo Drilling Spacing Units - Polygon inside another polygon from its boundaries

DanPatterson_Retired — Wed, 06 Dec 2017 16:19:36 GMT

No, modelbuilder only allows you to use scripts and tools that exist in arctoolbox. Your 'slow spot' is the unequal offset which will require a script of some form

Re: Create Pseudo Drilling Spacing Units - Polygon inside another polygon from its boundaries

coleblair — Wed, 06 Dec 2017 20:17:35 GMT

I know there are endless resources for scripting. however do you have a suggestions for a jump off point?

Re: Create Pseudo Drilling Spacing Units - Polygon inside another polygon from its boundaries

AbdullahAnter — Wed, 06 Dec 2017 21:13:41 GMT

There is another solution.If you have an advanced license.

First make the section boundary as polygon. And make the sub-boundaries as lines. you can use Feature To Line and Feature To Polygon (both Available with Advanced license)

then Select vertical lines and create 330 feet buffer . and select the horizontal lines and create 165 feet buffer . Then Merge the two input to one feature class.

Finally use Erase tool to get your polygon features . make the major section boundary as input feature and the output of merge tool as erase feature.

I hope that be helpful.