In this case, the data is 16 day from about 2000 to
present. So, on the order of 275 time steps. There are
daily products and annual products though, in wich case,
we are looking 12 to 4000+ time steps.
Jason, is the tile scheme you sent over used for all the
different resolutions? Looking at a few of them it looks
like that is the case.
- Dave
On Tue, Feb 26, 2013 at 7:48 AM, John Caron
<address@hidden <mailto:address@hidden>>
wrote:
Heres an image of this file.
questions about aggregations: how many time steps
will be in each aggregation ? how many different
aggregations (tiles?) will you serve?
On 2/24/2013 6:55 PM, David Blodgett wrote:
Sweet, thanks John. There was data in the tile,
but was hard to find... BORING, I know. Sorry
about that.
Here's a tile over the great lakes to give you a
coast to compare locations to.
http://e4ftl01.cr.usgs.gov/MOLT/MOD13Q1.005/2000.03.05/BROWSE.MOD13A1.A2000065.h11v04.005.2008238024700.1.jpg
http://e4ftl01.cr.usgs.gov/MOLT/MOD13Q1.005/2000.03.05/MOD13Q1.A2000065.h11v04.005.2008238031620.hdf
http://e4ftl01.cr.usgs.gov/MOLT/MOD13Q1.005/2000.03.05/MOD13Q1.A2000065.h11v04.005.2008238031620.hdf.xml
- Dave
On Feb 24, 2013, at 6:33 PM, John Caron wrote:
Hi:
Im hacking away at this, but the datafiles i
downloaded _seem_ to have nothing but missing
values. Or im doing something wrong. Can you
send me a file that you know has real data in
it. thanks
John
On 2/24/2013 9:22 AM, David Blodgett wrote:
Hi John,
Actually, I was assuming that the
sinusoidal projection was in there, doh!
That was based on gdal_translate creating
a geotiff with this projection info:
PROJCS["unnamed",
GEOGCS["Unknown datum based upon the
custom spheroid",
DATUM["Not_specified_based_on_custom_spheroid",
SPHEROID["Custom
spheroid",6371007.181,0]],
PRIMEM["Greenwich",0],
UNIT["degree",0.0174532925199433]],
PROJECTION["Sinusoidal"],
PARAMETER["longitude_of_center",0],
PARAMETER["false_easting",0],
PARAMETER["false_northing",0],
UNIT["metre",1,
AUTHORITY["EPSG","9001"]]]
There's a georeferencing section here
(http://www.gdal.org/frmt_hdf4.html) that
has a bit more info about gdal's
implementation. Might be something
helpful there? Looks like the ODL text
you point to is where its coming from.
4 and 5 are questions for Jason and maybe
Jordan. Guys?
- Dave
On Feb 23, 2013, at 1:22 PM, John Caron
wrote:
On 2/22/2013 2:07 PM, David Blodgett
wrote:
Welcome back John. Hope you had a
good trip!
thanks!
I actually just spent a bunch of
time with this the other day and have
been meaning to summarize what
I'm finding.
The first issue we are running
into is your #1 below. In this
case there
is an external xml file that
contains a lot of metadata, including
information about the projection
(sinusoidal), which is currently
unsupported by NetCDF-Java?
1) where do you get this xml file?
2) im looking at
MOD13Q1.A2000065.h00v08.005.2008238080422.hdf
MOD13Q1.A2000065.h00v08.005.2008238080422.hdf.xml
in your union subdirectory. The xml
file does not seem to have projection
info in it.
3) the internal ODL text
(StructMetadata) has
...
UpperLeftPointMtrs=(-20015109.354000,1111950.519667)
LowerRightMtrs=(-18903158.834333,-0.000000)
Projection=GCTP_SNSOID
ProjParams=(6371007.181000,0,0,0,0,0,0,0,0,0,0,0,0)
SphereCode=-1
...
which may be enough to calculate the
lat/lon values. Since this is the
best choice, lets investigate it
before we go down any other paths.
4) Can anyone track down the code in
the hyrax handler that does this? Or
does the hyrax handler actually link
in the hds-eos libraries ??
5) how confident are you that all the
files that you want to aggregate have
the same lat/lon geolocation ?
John