topic Re: Extent of a shapefile derived from XY coordinates is too small, doesn't match extent of baselayer, looking for help. in State & Local Government Questions

Extent of a shapefile derived from XY coordinates is too small, doesn't match extent of baselayer, looking for help.

PaulFrissora1 — Fri, 22 Dec 2017 16:32:13 GMT

I'm working on a project right now that requires me to verify the accuracy of point locations in a given area. I was given an excel spreadsheet to start with, so I turned it into a .xls and created an XY coordinate based shape file with it.

For reference, I made this layer in ArcCatalog, by right clicking on the .xls file and saying > Create Feature Class > From XY Table. I specified the right projection and XY axes.

The problem is that the extent of this shape file is really messed up. All 700+ points are within the same 1 foot by 2 foot scale/extent, when they should be covering an area of several hundred square miles. This is the extent of the points, and this is the extent of my base layer.

I've checked certain things but none of my troubleshooting seems to be working:

* Made sure that the map projections for the data frame, baselayer, and point layer are the same

* Coordinates are in Decimal Degrees

* The fields for the lat/long are numeric (double)

* The coordinates themselves are correct. I verified this by typing them into Google maps.

* Restarted ArcMap/Computer, problem is definitely with the file itself or the software.

* When I zoom in to the layer the point they appear to be in the form they'd be in if in the right extent.

Would it be better if I created a separate data frame, put the file in there, and then specified it to be the same extent?

What am I doing wrong here?

Re: Extent of a shapefile derived from XY coordinates is too small, doesn't match extent of baselayer, looking for help.

DanPatterson_Retired — Tue, 09 Jan 2018 23:44:54 GMT

Your first link... the units aren't in feet, they are decimal degrees. I suspect that something hasn't been defined properly. The first links data should have been defined as a geographic coordinate system (ie GCS NAD83 or GCS WGS84 depending on the datum for your location) not a projected coordinate system . The second link's extents are in a projected coordinate system.

Don't skip the step of defining what the coordinate system IS and not what you want it to be.

Define Projection .... tell it what it is.

Project make it what you want it to be, once it knows what it is

Re: Extent of a shapefile derived from XY coordinates is too small, doesn't match extent of baselayer, looking for help.

PaulFrissora1 — Tue, 09 Jan 2018 23:53:30 GMT

Thanks! This post only got approved a week after I got it figured out. In ArcCatalog I didn't specify to create the Shapefile in the 1984WGS projection, instead I was trying to convert it within ArcMap. But yeah, this is what I should have been doing.