I have a polygon and a set of datapoints that fall both inside and outside the polygon. The points each have XYZ data that I want in the output. I want to select only those datapoints that fall within 1km of the polygon edge/boundary. Any ideas on what Arc toolbox feature to use? I am operating with ArcMap 10.3.1
Using the select by location tool would be my recommendation for capturing the points you want with 1km of the polygon boundary. A good resource is through Esri's help page.
They provide Steps for using Select By Location
Use the following steps to apply the Select By Location tool.
Click Selection > Select By Location to open the Select by Location dialog box.
The Select By Location tool
Choose the type of selection that you want to make. Click the drop-down arrow to see your choices. Choose your desired selection type Identify the target layer(s) from which features will be selected and check them on (Display). Choose the spatial relationship rule that will be used for selection.
Select the spatial relationship rule from this list. Specify the source layer that will be used to select features from the target layer.
Setting the source layer for Select By Location To complete your Select by Location specification, you can optionally specify if you want to Use selected features in the source layer to identify the features to select. Use a buffer distance in your search (buffer distances are only used with some selection options).
I recommend creating a buffer around the boundary and then using the select by location tool to obtain the points that fall within the buffer region. I am however not sure whether you are looking for points inside or outside the boundary or both.
If you are looking for points outside the boundary:
Use select by location to select points within the original boundary and exclude them from further selection.
Create the 1 km buffer around the boundary and the select the points that fall within the buffer.
A similar approach can be used to obtain the points inward of your boundary up to 1km.
if you want both:
then create a new poly line feature to mimic the boundary of the polygon (Reproduce the polygon boundary as a poly line).
Create the 1000 m buffer around it and select the points that fall within the buffer. I have done similar work a while back at the uni and I am confident this should work well.