[postgis-devel] Re: [postgis-users] Re: Buggy transform() function in 1.0RC1 ?

[Gino Lucrezi]

> Nicolas, in the pdf you sent (good work!) you tell previous
postgis 
> versions worked fine. I took a look at older definitions
and I 
> found out that both +pm and +lon_0 have the same value
> (2.337229166666667). New definition changed the +pm to Paris
(instead 
> of literal number) and that seems to have broken things up.

Here is the definition in pj_datums.c:

C_NAMESPACE struct PJ_PRIME_MERIDIANS pj_prime_meridians[] = {
    /* id        definition                         */
    /* --        ----------                         */
    "greenwich", "0dE",
    "lisbon",    "9d07'54.862\"W",
    "paris",     "2d20'14.025\"E",
    "bogota",    "74d04'51.3\"E",
    "madrid",    "3d41'16.58\"W",
    "rome",      "12d27'8.4\"E",
    "bern",      "7d26'22.5\"E",
    "jakarta",   "106d48'27.79\"E",
    "ferro",     "17d40'W",
    "brussels",  "4d22'4.71\"E",
    "stockholm", "18d3'29.8\"E",
    "athens",    "23d42'58.815\"E",
    "oslo",      "10d43'22.5\"E",
    NULL,        NULL
};

I noticed that Paris is written all in lower case, i.e. paris instead of Paris.
Maybe that is part of the problem?
With the cs2cs utility it aborts the conversion.

> 	1) +pm=Paris +lon_0=0
> 	2) +pm=2.337229166666667 +lon_0=2.337229166666667

> It would help testing both with different proj4 versions.
> I don't whether they should be equivalent, but really do
not look 
> like they are (unless Paris resolves to 2.337*2).

Not all parameters are really used in all situations.
See, for example, this entry in Proj4's bugzilla:

http://bugzilla.remotesensing.org/show_bug.cgi?id=510

I had similar issues in the past with reprojections, see here:
http://postgis.refractions.net/pipermail/postgis-users/2004-June/005040.html


Gino Lucrezi
Penta Consulting Services Srl

P.S. I am going to unsubscribe from this list in the next few days. I'm changing job, and I won't be working with GIS systems in the new job.