[OSRS-PROJ] lib call results differ from exec results

Gerald I. Evenden gerald.evenden at verizon.net
Mon Jul 14 16:31:56 EDT 2003

First of all, I do not recall ever specifying standard parallels
for Albers.  Of course I can always be proven wrong by some ancient

Program 'lproj' is what I distribute currently with the libproj4
library and is the same as 'proj' except that the approximation
output is omitted and there are no external default and reference
file lookups.  There may have been a "default" parallels in those
files for identifiers relating to conterminous US mapping but
nothing just for a basic projection---it would have been referred
to with a special name and not simply the projection name.
Things in these files were mostly grid reference systems.

The system you are using must be loaded with some odd macros
so as to interpret things like:

projXY xy;    ????

Hmmm, A storage declaration, maybe, but I've never seen one in
the middle of a block but, then again, I can't find a rule that
they can't be.  Verrry interesting.  Never mind.

Try specifying stardard parallels as well as central meridian
in both of your cases and see what turns up.

On Mon, 2003-07-14 at 13:57, Sharon Mingus wrote:
> --- "Gerald I. Evenden" <gerald.evenden at verizon.net>
> wrote:
> > First of all, I can't see how you can use Alber's
> > Equal Area
> > conic without specifying the standard parallels.
> > 
> Aren't there defaults?  I'm not a projections guru and
> pumping coords into proj & pj_fwd without standard
> parallels is producing results.  I'm just curious why
> they are different.
> > ./lproj +proj=aea +ellps=clrk66
> What is "lproj"?  I don't have that as a binary.
> > libproj4 system
> > <./lproj>:
> > projection initialization failure
> > cause: conic lat_1 = -lat_2
> > program abnormally terminated
> This is not happening to me.
> > 
> > Is what I get on my machine.  Of course we are not
> > using the
> > same basic animal but it would seem to me that the
> > software
> > used should complain about the usage parameters. 
> > Without
> > knowing the parallels, no computations were
> > possible!
> > 
> > Out of curiosity, what programming language is used
> > below?
> language = "C"
> > 
> > On Mon, 2003-07-14 at 12:52, Sharon Mingus wrote:
> > > I'm using the latest cvs libproj for
Gerald I. Evenden <gerald.evenden at verizon.net>

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