[Proj] transformation in c

Gerald I. Evenden geraldi.evenden at gmail.com
Thu Mar 26 09:14:21 EST 2009

On Wednesday 25 March 2009 10:57:59 pm Richard Greenwood wrote:
> On Wed, Mar 25, 2009 at 11:01 AM, Gerald I. Evenden
> <geraldi.evenden at gmail.com> wrote:
> > On Wednesday 25 March 2009 11:48:01 am Frank Warmerdam wrote:
> >> Stanislav,
> >>
> >> There is pretty good information on using the PROJ C API at:
> >>
> >>   http://trac.osgeo.org/proj/wiki/ProjAPI
> >
> > I can't help but find the above website very weak and merely an exercise
> > in reformulating the previously simple usage of proj and then having the
> > contempt to call pj_fwd, pj_inv and pj_init obsolete.
> >
> > To compound the issue of pj_fwd/inv, these functions are used withing
> > pj_transform!  So how can they be obsolete yet required by the replacing
> > procedure?
> I would discourage the use of pj_fwd and pj_inv. If "obsolete" is
> offensive, how about "private". It is so provincial in this day and
> age to think that we merely project and un-project without concern for
> datum.
> Regards,
> Rich

That, of course, is the most ignorant and absurd statement and underlies my 
decision to sign off this list.  I am tired of responding and otherwise 
wasting my time writing emails in an attempt to correct this erroneous 

Nowhere in the definition of a cartographic projection is there any aspect of 
datum involved.  Many books and articles have been written about cartographic 
projections and datums are rarely mentioned and when they are, it is in 
association with the status of the data involved and not in the act of the 
cartographic projection.

Enough said here as I am obviously writing to the proverbial brick wall of 

Anyone who wants to talk about cartographic projects knows my email address an 
I am always willing to discuss issues germane to this subject.  I am also 
willing to listen and discuss issues related to datum transformations but 
*not* when is assumed that they are part of the projection process.

Yes, I am taking my marbles and going home.


The whole religious complexion of the modern world is due
to the absence from Jerusalem of a lunatic asylum.
-- Havelock Ellis (1859-1939) British psychologist

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