Splitting a Polygon into Sections.

[Atlas_Beetle]

I split a polygon feature into sections using the Fishnet tool, but it skips a section for some reason. Why is that? Also can I rotate the angle of my DEM without messing up my other layers or generate the grid at an angle so it cuts the canyon feature into more perpendicular slices? Finally if I tell it to make the sections a certain width rather than make a certain number of them, what will it do if the length of the polygon does not perfectly divide into that section size? Will it start at one end and at the other end have a shorter section? Which side will it start at?

[DanPatterson]

dont' rotate the dem, rotate the grid

Details on what happens whether you use fixed width/length etc are covered in the help topic.

Create Fishnet (Data Management)—ArcGIS Pro | Documentation

from Pro's help but the tool is similar in arcmap.

If you run the tool, you will find, that the progression of the polygons is left to right (west to east) for a single row.

You will have to experiment to get things split as you want.

as for the section being missed, check your input parameters to the tool and run Check Geometry on your polygons to ensure that they are clean

[Atlas_Beetle]

Does "rotating" the grid pretty much just change how the data frame is displayed rather than mess with any of the spatial referencing? That sounds perfect for me.

[DanPatterson]

rotating a raster coluld entail small but significant data changes... rotating a vector doesn't, plus it takes less time to rotate vector data

[Atlas_Beetle]

Well if just adjusting the angle of the data frame display makes the fish net grid generate at a better angle I'm happy for the help. Thanks again as always.

[DanPatterson]

you can adjust the angle of the fishnet.... that is what I am referring to

[Atlas_Beetle]

From the built in help, I see that I do this by changing the y-axis cord...but how do I do that if I want to rotate things say 17 degrees counter clockwise?

Also it won't let me specify that I only want one row, but the number of columns to be determined by a cell length. Am I setting that up wrong? 

[DanPatterson]

How Create Fishnet works—ArcGIS Pro | Documentation

set the cell size width and height, then specify the number of rows and columns

Define the cell width and height as above, but additionally enter the number of rows and columns.