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No problem, could you please post these datum definitions or give me a link?
Original comment by vadp.d...@gmail.com
on 2 Apr 2014 at 6:48
Actually a few samples would help as well
Original comment by vadp.d...@gmail.com
on 2 Apr 2014 at 8:59
Corrego Alegre:
http://georepository.com/datum_1074/Corrego-Alegre-1961.html
http://georepository.com/datum_6225/Corrego-Alegre-1970-72.html
SAD
http://georepository.com/datum_6618/South-American-Datum-1969.html
SIRGAS2000
http://georepository.com/crs_4674/SIRGAS-2000.html
Samples can be downloaded from
http://www.mar.mil.br/dhn/chm/cartas/download/cartasbsb/cartasl_eletronicas_Inte
rnet.htm (most files are WGS84 though)
Original comment by gay.to...@gmail.com
on 2 Apr 2014 at 11:22
Unfortunately for the link:
http://www.mar.mil.br/dhn/chm/cartas/download/cartasbsb/cartasl_eletronicas_Inte
rnet.htm
I'm getting:
"A página requisitada
"/dhn/chm/cartas/download/cartasbsb/cartasl_eletronicas_Internet.htm" não
pôde ser encontrada."
It would be great if you'd post some links to specific files. At least one
sample per each datum.
Original comment by vadp.d...@gmail.com
on 3 Apr 2014 at 8:34
I discovered the same list night as well, seems like the site is in
reconstruction.
Since I have no idea if any links will work at the moment I have attached a
file in Corrego Alegre projection, I have round 2000 KAP files, so looking
through all for different formats are very time consuming. If I come across
other formats I'll post them here
Original comment by gay.to...@gmail.com
on 3 Apr 2014 at 11:25
Attachments:
And another
Original comment by gay.to...@gmail.com
on 3 Apr 2014 at 2:14
Attachments:
OK for COA datum the definition should be:
datum,COA,"+ellps=intl +towgs84=-206,172,-6,0,0,0,0"
I'll update data_bsb.csv accordingly.
Could you please send me some samples for other datums?
BTW You could use map2gdal.py <file> to see file's datum and projection. It
leaves .vrt file then which you can delete safely.
Original comment by ssvadim@gmail.com
on 3 Apr 2014 at 4:05
Seems like COABR is an alias for COA, I saw them both in the list when I did:
for i in `find . | grep KAP`; do head -n 15 $i | grep KPN; done | less
I have some files with a mysterious ASTRONOMICAL DATUM, and one UNKNOWN, seems
like I have no files with SIRGAS or SAD at the moment - apart from that all
files are NAD and WGS84
Original comment by gay.to...@gmail.com
on 3 Apr 2014 at 6:48
Thanks for you "find" script. Here is my modification:
IFS=$'\n' sh -c 'for i in `find . -iname \*KAP|sort`; do head -n 15 "$i" | echo
"$i:" `grep KNP|grep -v WGS`; done'
I wonder if you'd post your "ASTRONOMICAL DATUM" sample.
Original comment by ssvadim@gmail.com
on 6 Apr 2014 at 12:23
See attached
Original comment by gay.to...@gmail.com
on 6 Apr 2014 at 12:35
Attachments:
As this chart covers Tern Island, then my guess is that that datum is
equivalent to:
ASTRO TERN Island (FRIG) 1961
(http://earth-info.nga.mil/GandG/coordsys/onlinedatum/CountryPacificTable.html#T
RN)
So the definition should look like:
datum, ASTRONOMIC DATUMS (GENERAL), "+towgs84=114,-116,-333,0,0,0,0
+ellps=intl",
Original comment by ssvadim@gmail.com
on 6 Apr 2014 at 3:20
As per a note at the chart 19016_1.KAP and some other similar ones from the
same source I can conclude that the main features there "can be considered
equivalent to <...> WGS 84".
More the KAP file does not contain easting/northing data (DTM).
So, there is no sense in including "ASTRONOMIC DATUMS (GENERAL)" into
data_bsb.csv as a chart with such a datum will be converted to WGS 84 by
default.
Original comment by ssvadim@gmail.com
on 7 Apr 2014 at 1:54
BTW an useful note from http://www.thsoa.org/pdf/cgs_afe_12.pdf:
"Independent Astronomic Datums
Besides the <...> principal datums <...> there are a
number of independent astronomic datums that were established to
control small detached surveys on offlying islands or other remote
places. Among these may be mentioned several small harbors in the
Aleutian Islands, Nushagak Bay, Cape Newenham to north of the Kus-
kokwim River, Norton Sound, Port Clarence and the Pribilof Islands.
Names are not usually appended to such datums but they are referred
to as "Independent astronomic datums."
Original comment by ssvadim@gmail.com
on 7 Apr 2014 at 1:57
Fixed in 95c344b8fdb0
Original comment by vadp.d...@gmail.com
on 7 Apr 2014 at 2:35
Original issue reported on code.google.com by
gay.to...@gmail.com
on 1 Apr 2014 at 4:24