datums

[Gerald I. Evenden]

This note was originally to Carla Elenz but I have given up trying
to get my local mail handler to process the return address so I hope
she reads grassu.  Sorry for the inconvenience.

From: gie at charon.er.usgs.gov (Gerald I. Evenden)
Message-Id: <9408171426.AA00671 at charon.er.usgs.gov>
Sender: grass-lists-owner at moon.cecer.army.mil.
Reply-To: grassu-list at moon.cecer.army.mil.
Precedence: Bulk
To: grayling!celenz
Subject: Re:  datums

>Date: Tue, 16 Aug 94 10:50:58 EDT
>From: grayling!celenz at uxc.cso.uiuc.edu (Carla Elenz)
>To: cerl!amber.cecer.army.mil!charon.er.usgs.gov!gie at uxc.cso.uiuc.edu
>Subject: datums
>
>Hello Jerry,
>
>You sent a message some time ago to the grassu-net concerning
>using nad2nad in proj.4.  I am not a grass guru, just a

I'm not one either, I've only used GRASS once and I was stumped
because of lack of documentation.

>struggling user, and have been trying in vain for several months
>to find a way to convert maps between nad27 and nad83, as some
>of my maps are in each and I would like to standarize.  Unfortunately,
>I cannot ftp from my site (evidently I don't have the right kind
>of phone lines). Can you fill me in on whether proj.4 is the
>program I need and how I can get it.  I'm sure I will need help
>in installation also.  THank you very much.

The subset of the PROJ.4 system that is of most use to you is the
program *nad2nad*.  As its name infers, it will convert data between
the North American datums, but it is restricted to the borders of
the U.S..

As far as installation, the PROJ.4 makes every attempt to be ANSI-POSIX
compliant and uses GNU's configure procedure to create Makefiles and
installation script modifications.  So far, the only system that I have
found which gives me fits is SGI.  It is recommended and "guarantees"
installation if the *gcc* compiler installed.  This is a requirement on
older Sun systems that do not have an ANSI compliant compiler.

For getting a copy of PROJ.4, I can make 3.5 or 5.25 (1.2, 1.44 AT)
diskettes of the system in compressed tar format.  Full code source and
NADCON tables requires 2 diskettes and *PostScript* documentation
requires 2 additional diskettes.  If you have a system that has a
floppy reader, this should work.  Send to me at the address below
a SASE mailer with selected number of formated diskettes to the
address below.  As an alternative to the "stamped" part of SASE,
include a $2.90 stamp for return "Priority Mail" postage.

I am retired, so the above procedure eliminates out-of-my-pocket
expense.  There is not a convenient way for me to do this kind of
distribution at the USGS, where postage and diskettes would be
"on the house." :-(

>Carla Elenz
>Environmental Office
>Camp Grayling, MI
>
>(517) 348-7621 ext 3306
>
>grayling!celenz at cerl.cecer.army.mil

Gerald (Jerry) I. Evenden   Internet: gie at charon.er.usgs.gov
voice: (508)563-6766          Postal: P.O. Box 1027
  fax: (508)457-2310                  N.Falmouth, MA 02556-1027