Notifications
Clear all

Coordinates

14 Posts
11 Users
0 Reactions
1 Views
not-my-real-name
(@not-my-real-name)
Posts: 1060
Customer
Topic starter
 

I received a coordinate file for a project yesterday. They looked a little strange. When I plotted one pair for a test it looked like this.

Attached files

 
Posted : 25/03/2016 4:46 am
(@holy-cow)
Posts: 25292
 

I wonder where one gets a license to do legal surveys in that locale. Perhaps it's the new site for Buoystown.

 
Posted : 25/03/2016 4:49 am
(@james-fleming)
Posts: 5687
Registered
 

Holy Cow, post: 364075, member: 50 wrote: I wonder where one gets a license to do legal surveys in that locale. Perhaps it's the new site for Buoystown.

Not a license, but....

http://www.boem.gov/

 
Posted : 25/03/2016 5:25 am
(@ron-h)
Posts: 2
Registered
 

What datum are the coordinates on....UTM? Or perhaps from a CAD file and the N/E reversed to represent x/y? Just a thought....

 
Posted : 25/03/2016 6:06 am
(@tom-adams)
Posts: 3453
Registered
 

I don't know who did what. When I look @ someone else's work, and some things don't make sense, the first thing I do is try to find out what I did wrong. If I can't find anything, I try to figure out what they may have done to get their screwy results. I have a lot easier time if I figure out exactly what bonehead thing someone most likely did.

 
Posted : 25/03/2016 6:41 am
 rfc
(@rfc)
Posts: 1901
Registered
 

not my real name, post: 364073, member: 8199 wrote: I received a coordinate file for a project yesterday. They looked a little strange. When I plotted one pair for a test it looked like this.

At first I thought this was easy. NEZ rather than ENZ (or some similar coordinate transposition).
But 73N x 36W doesn't look much better than 36N x 73W:-D

 
Posted : 25/03/2016 6:48 am
 rfc
(@rfc)
Posts: 1901
Registered
 

Or, worse yet....
36N x 73E (just north of Islamabad)!

 
Posted : 25/03/2016 6:52 am
 rfc
(@rfc)
Posts: 1901
Registered
 

35S x 73W? Santiago Chile?

 
Posted : 25/03/2016 6:55 am
 rfc
(@rfc)
Posts: 1901
Registered
 

Searching for MH370?

 
Posted : 25/03/2016 7:00 am
 ddsm
(@ddsm)
Posts: 2229
 

Perhaps they are using Washington DC as the longitude base???
https://en.wikipedia.org/wiki/32nd_meridian_west_from_Washington

DDSM:-S

 
Posted : 25/03/2016 7:05 am
(@mathteacher)
Posts: 2081
Registered
 

That wouldn't be from the NC Bridge Inventory file, would it? Several years ago I wrote software to convert federal bridge inventory text files to kml. There was a bridge in Brunswick County whose official gummit coordinates were in the middle of the Atlantic Ocean.

 
Posted : 25/03/2016 7:27 am
(@itsmagic)
Posts: 217
Registered
 

If a client or colleague want to send me a coordinate file, I always ask for the metadata that describes the coordinate system. When sending a coordinate file, I always include this information.

This avoids uncertainty, and more importantly, liability.

For instance, I have clients that use UTM mapping coordinates scaled to ground (and still labelled as UTM) because "that is the way we have always done it". If they do not know why I need the metadata, I explain it to them using examples from my collection of coordinate problem data sets that I have collected over the years.

One of our responsibilities as professionals is to provide guidance.

 
Posted : 25/03/2016 11:29 pm
(@bill93)
Posts: 9834
 

itsmagic, post: 364241, member: 468 wrote: I always ask for the metadata.

Yes, sir. Did you want your room to be 68 Fahrenheit or 68 Celsius?

 
Posted : 26/03/2016 10:58 am
(@skwyd)
Posts: 599
Registered
 

Bill93, post: 364287, member: 87 wrote: Yes, sir. Did you want your room to be 68 Fahrenheit or 68 Celsius?

Or 68 Rankine, or possibly 68 Kelvins (for those that like their rooms very chilly).

 
Posted : 28/03/2016 10:51 am