topic Re: Calculate Geometry: Returning Same Value For All Attributes in Data Management Questions

Calculate Geometry: Returning Same Value For All Attributes

MikeMichalek1 — Tue, 23 Sep 2014 14:08:48 GMT

I am trying to convert northing/easting coordinates from Michigan Geo-Ref (m) to Michigan State Plane International (ft). I followed a helpful guide (below), which helped me do this conversion.

Lat Long to Northing Easting

After switching projections in ArcCat. it was time to calculate geometry for my northing and easting fields. So as the guide said I followed these instructions.

In the Calculate Geometry dialog select these options:

a. Property: X Coordinate of Point

b. Coordinate System: Use coordinate system of the data frame (in which will be listed your Michigan North system)

c. Units: meters (IN MY CASE FT)

Then click OK.

After doing so all of my attributes switched to the same value (i.e., northings of 20587707.37 and eastings of 26246789.6853).

What am I doing wrong here? Is there a way that I can run this differently to produce different values?

Thanks for your help,

Mike

Re: Calculate Geometry: Returning Same Value For All Attributes

MelitaKennedy — Tue, 23 Sep 2014 17:13:42 GMT

Wait, what do you mean when you say you switched projections in ArcCatalog? Did you use the data's property page to change the coordinate system definition. That just updates the metadata, not the data's coordinate values. If that's what you did, undo it (define the data back to Michigan GeoRef). Add it to ArcMap and set the data frame's coordinate system to the state plane that you want to use.

Open the attribute table, select a field (may need to create a new one) and right-click it to access the calculate geometry dialog. Use the data frame's coordinate system when calculating the field.

Melita

Re: Calculate Geometry: Returning Same Value For All Attributes

MikeMichalek1 — Tue, 23 Sep 2014 17:24:58 GMT

Melita,

Thanks for your reply. I didn't change the metadata. I created a new feature class from a imported .CSV file. From there I assigned my X and Y fields and the original coordinate system (Michigan GeoRef - m).

I simply want to bring in my coordinates in GeoRef - m and convert them to Michigan State-Plane International - ft.

Re: Calculate Geometry: Returning Same Value For All Attributes

MelitaKennedy — Tue, 23 Sep 2014 17:30:51 GMT

Hmmm, I think there was a bug with the calculate geometry, but I remember it occurring with lat/lon data, not projected data. I would double-check that the csv imported/converted correctly. If you calculate the GeoRef values instead, do they look correct and match the original csv?

Re: Calculate Geometry: Returning Same Value For All Attributes

MikeMichalek1 — Tue, 23 Sep 2014 17:59:08 GMT

I have reworked the process a couple of times now and have gotten "calculate geometry" to work.

Now it seems my issue is projection. I'm working with Northing/Eastings from Northern Michigan and my data is being projected in Northern Quebec after the Michigan GeoRef - m TO Michigan State Plane International - ft conversion.

Re: Calculate Geometry: Returning Same Value For All Attributes

MelitaKennedy — Tue, 23 Sep 2014 18:04:49 GMT

Hmmm, I would try calculating the lat/lon values or adding the original data to ArcMap and checking the lat/lon values by Identifying a feature and changes the units to decimal degrees or changing the display units to decimal degrees. I have a feeling that there's something wrong in the original feature class. Can you post a sample point from the original and what values you're getting in MI North (int'l feet)?

Melita

Re: Calculate Geometry: Returning Same Value For All Attributes

MikeMichalek1 — Tue, 23 Sep 2014 18:29:38 GMT

I figured it out. ESRI does not have the same projection file for Michigan GeoRef as the State of Michigan (survey data) giving me error. Additional error came in when I chose to use "Calculate Geometry", which does not calculate international feet, only US feet when using my chosen projection.

Thanks for your help and continued interest today.