topic Re: Grid Points in Data Management Questions

Grid Points

CindyCarter-_Davis — Fri, 08 Apr 2011 15:10:40 GMT

Hi, I'm a self- taught ArcGIS user (10.0) and I would like to create grids of points. I tried to use the measured grid option, by turning the grid into a series of points, but when I try to ungroup them so I can just show the ones in my project area ArcGIS crashes.... any ideas? Thanks so much for the help!

Re: Grid Points

michaelcollins1 — Fri, 08 Apr 2011 16:23:55 GMT

It doesn't crash when I try it.
I'm not sure what you are trying to accomplish here. You could create a table of grid coordinates in excel, then use Arc catalog to import the table as a point shape file.

Re: Grid Points

CindyCarter-_Davis — Fri, 08 Apr 2011 17:03:10 GMT

I guess I didn't explain myself very well. I am trying to overlay proposed shovel test locations (I'm an archaeologist) on a project area in 30 meter intervals. Normally, I just create points by hand, but this project area requires more than 2000 shovel tests... the measured grid shows what I need, but I can't seem to convert the graphic so that I can delete extraneous points, and only show the "dots" in my project area... I know that there is an easier way, but can't seem to find one other than creating each stp point by hand..

Re: Grid Points

MelitaKennedy — Fri, 08 Apr 2011 18:15:08 GMT

I guess I didn't explain myself very well. I am trying to overlay proposed shovel test locations (I'm an archaeologist) on a project area in 30 meter intervals. Normally, I just create points by hand, but this project area requires more than 2000 shovel tests... the measured grid shows what I need, but I can't seem to convert the graphic so that I can delete extraneous points, and only show the "dots" in my project area... I know that there is an easier way, but can't seem to find one other than creating each stp point by hand..

How about the Create Fishnet tool? It creates a polyline or polygon feature class, but there's an option to create label points. If you use the polyline option with create label points, you'll get a point feature class.

Melita

Re: Grid Points

CindyCarter-_Davis — Fri, 08 Apr 2011 19:29:35 GMT

Melita,
Thanks so much, it worked great!!! You just saved e abut 8 hours of making dots

Re: Grid Points

EricGriffis — Mon, 08 Jul 2013 19:56:33 GMT

Is there a tutorial of how to do this? No one in our GIS department seems to know how to do this. Thanks.

Re: Grid Points

MelitaKennedy — Mon, 08 Jul 2013 20:27:54 GMT

I don't know if there's a tutorial. The Create Fishnet tool is a little complicated possibly because it's modeled after the similar command in ArcInfo workstation. There's a decent topic that has some pictures of what happens if you set a rotation for example.

How Create Fishnet works

You can build the fishnet in any coordinate system. Sometimes it's easier to build a lat/lon one while at other times, it's easier to build one based on the coordinate values of a projected coordinate system (like UTM). You need to have the spatial extent and the "cell size" or distance between grid lines. Alternatively, you can have a lower left corner plus how many 'rows' and 'columns' you want. If you have the later, the tool will figure out the separation distance for you.

Note: If I remember correctly, the dataset created by the tool won't have a defined coordinate system, so you'll want to do that first with the Define Projection Tool.

Melita