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XY Conversion from Intergraph NAD_1983_3TM114

October 21 2008 | 2 comments
Categories: Map Data

I am REALLY hoping someone can help me! I have event data that has address information. This address information is converted through Intergraph into a a "Units of Resolution" measurement (I haven't heard of this before). This is then transformed into XY coordinates in meters for mapping purposes (NAD_ 1983_3TM114) using the following formula:

XTM =((A2+2147483648)/25000)-36000 where A2 is your original coordinate
YTM = ((B2+2147483648)/25000)+5834000 where B2 is your original coordinate

I need a formula that will translate either the Raw X/Y data into DMS or the 3TM X/Y Data into DMS. I'm not sure which way is the better way to go and I don't know what the Units of Resolution are. I have attached a file (RAW XY are in units resolution)

Thanks in advance for ANY help!!

Mapping Center Answer:

Honestly, I've never seen or heard of this and I'm just Googling and not finding anything.  Your data need to be in decimal degrees for the XY Events to be processed. Since Intergraph didn't produce that it's beyond my expertise. 

Also I just looked at your coordinate list.  They don't look geographic to me.  The conversion formula for YTM looks flawed.  Maybe these are supposed to be UTM coordinates units = meters, but I wouldn't know what zone?

UOR's posted by Eadie Kaltenbacher on Nov 25 2008 3:02PM
Units of Resolution are a Microstation property. I ran into this problem when I was importing data from Intergraph into ESRI, but it turned out the Intergraph data was actually being generated from a Microstation DGN file (is this I/Leads data by any chance?)
We worked with Intergraph to determine our formula for converting to real-world units. In our case the UOR's were set up in metric, so the conversion involved dividing by 3.048 to get from meters to feet.
Once you get your coordinates in order, you can display them in ArcMap. Rather than converting your data to DMS, make your Excel spreadsheet into a CSV and add it to a projected map document. Then right click on the table (visible in the source tab) and select Display XY Data. Choose the newly calculated fields to represent your X and Y coordinates. I think your field names can't start with a number.
Wow! Thanks! posted by Aileen Buckley on Nov 25 2008 3:04PM
Thanks for the info, Eadie!

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