North American Network Operators Group

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RE: Converting from telco Major-V, Major-H coordinates to Lat Long

  • From: Stewart, William C (Bill), RTSLS
  • Date: Mon Sep 29 15:34:42 2003

Pete Templin wrote: 
> Very rusty memory cells on this, but I think the mileage is 
> 0.1 * sqrt ((delta-V)^2 + (delta-H)^2)).  
> That's assuming same LATA, IIRC.

Close.  It's
	sqrt ( 0.1 * ((delta-V)^2 + (delta-H)^2)) )
and it doesn't care about LATAs.
It's mostly accurate in the US middle 48 states and 
nearby parts of Canada and Mexico.


http://datec.web.att.com/faqs/telecom.htm has more information,
not all of it correct.

Telecordia has pictures 
http://www.trainfo.com/products_services/tra/vhpage.html
and will sell you more documentation and software,
though they don't seem to make it easy :-)
They've also got some material on issues with the 
newer coordinate systems such as WGS-84.

Several other people all sell it - most of it's bundled with
databases of NPA-NXX.

http://article.gmane.org/gmane.comp.gis.proj-4.devel/26
points to the free OpenMap software, which has a converter.

http://article.gmane.org/gmane.comp.gis.proj-4.devel/19
has Fortran code!

Google will tell you more.

----
A long, long time ago, in a phone company far, far away,
I worked with some people who decided they had to go
reconstruct the algorithms used to generate these coordinates,
and we had some programs that could calculate translations.
Any records I have on that were probably backed up on a 
9-track tape somewhere before the department moved to another building,
though it's possible that they still exist on an account
I no longer have access to on a machine that does still exist
but is no longer as cutting-edge as it was in 1993.