[Proj] datum shift files confusing
gdt at ir.bbn.com
Sat Dec 9 21:14:42 EST 2006
The datum shift files in the ftp server are confusing. The top page
says to use proj-datumgrid-1.3.zip, but doesn't point out that both
are superceded by proj-datumgrid-1.3. This is particularly
unintuitive since .tar.gz changed to zip.
On inspection, I concluded that the diff from proj-nadus-10 to
proj-nad27-1.2 resulted in:
addition of ntv1_can.dat
addition of null.llv
Going from proj-nad27-1.2 to proj-datumgrid-1.3 resulted in:
addition of nzgd2kgrid0005.gsb
changing of README to clarify extent of provided files.
I think it would help to
add in parens at end of description of datumgrids
"(supercedes and extends proj-nadus and nad27)"
The FAQ refers to proj-nad27-1.1 still.
I've updated pkgsrc to use proj-datumgrid-1.3, but thought I'd share
what I figured out in case it's helpful to someone.
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