1,884 reputation
715
bio website staff.acecrc.org.au/~mdsumner
location
age
visits member for 3 years, 9 months
seen 16 hours ago

R, Manifold, GDAL, also interested in Python, topojson/D3 and NetCDF/HDF


Feb
7
comment how to create CF-compliant NetCDF from ESRI Grid?
GMT is a really weird variant that drops the array dims and requires the client to reinstate it, I doubt that it's what you want
Feb
5
comment Can I just swap out a .prj file to reproject a shape file?
No, reprojection needs a source and a target. What you suggest would simply reassign the source metadata that is assumed to represent your data as they are. (Sometimes you need to do that but not here). It is perhaps a variant of that cs in PRJ that karto does not understand, but that is a different problem. Try spatialreference.org to explore the zoo
Feb
4
comment Units of gBuffer from rgeos package
Yes your map projection is in units of metres.
Jan
28
comment Is there anyway to stack or merge .hdf files in R Studio?
Check out gdalUtils package and you need to know whether hdf4 or hdf5 and install other tools for the package to call
Jan
23
comment How to sample a 3D raster along a 3D path (or 4D raster along 4D path)?
I've done this in R if you want to start looking beyond your stated software. The stuff I have is very specific to a particular 4D data set, but it wouldn't be too hard to adapt. Adding transformations for xy is also pretty straightforward. Want to expand on what the "projection issues" are?
Jan
12
comment R or QGIS? Measuring elevation at points on DTM surface
extract(my.raster, AB) - here AB can be a matrix of two columns and two rows (one row each for points A and B), also you should only need raster(out.file) to read it in
Dec
29
comment Matching GPS tracks
Check out strava
Dec
28
comment Why is ArcGIS called ArcGIS?
"In the beginning", ha.
Dec
17
comment How to convert WGS84 to UTM when the study area covers 4 UTM Zones: 43- 46?
this is the right answer :)
Dec
17
comment Negative UTM easting
There should be no problem with a coordinate slightly outside a given UTM zone. Negative eastings can be fine, it actually depends on the offset values applied to a given UTM coordinate system (there are infinitely many possible systems). I don't think anyone can help without a specific example of where things go wrong, you might as well use PROJ.4 or the python bindings for GDAL to do this unless you really want this question to apply specifically to that Turbo87 software. At least give a specific lat, lon, zone and domain width and length and resulting corners so someone can reproduce.
Dec
16
awarded  Enthusiast
Nov
14
comment Longitude range NETCDF vs ASCII
gis.stackexchange.com/questions/37790/…
Nov
14
comment Longitude range NETCDF vs ASCII
Generally you need to crop one half and shift that, or use a projection that spans the region of interest, but how you do that depends on the software. Is arcgis part of the question, or are other options of interest?
Nov
10
awarded  Yearling
Nov
9
comment Merge overlapping DEMs with irregular boundaries
I have no idea where this is, I wonder what this would look like if you just plot them all together, rather than the merged result. Then you could desribe better what you expect, I think. I would also provide the gdal_merge command you use, and btw no need to convert to tif since GDAL will do that anyway right? Probably you want gdalwarp to do a non-simple merge.
Nov
9
comment Merge overlapping DEMs with irregular boundaries
Well doesn't it depend on what the coverage of each input is in the first place? What does that look like when you plot them together?
Nov
4
comment gdal_translate- why jpg compressed tif is 2 times greater than jpg file?
For me they turn out the same size, I think you need to establish an actual example to demonstrate what you are seeing, or perhaps at least give us the gdalinfo output of test.tif.
Nov
1
comment Arctic EPSG:4326 map projection?
I just mean generally for visualization and reprojection, I'm not familiar with Tableau.
Oct
31
comment Arctic EPSG:4326 map projection?
What is the ice data? Many products are delivered in a native polar stereographic projection (there's practically a standard for NSIDC/SSMI/AMSR-E, which is a rare happy bonus) that would be a better choice if that works for you. They tend not to be delivered with metadata included, but it's easy to find/apply. Are you just wanting to view the data or ultimately serve it up somehow? QGIS and R are good alternatives, but gdal ties it all together as usual.
Oct
24
comment How to create random point in according polygon for each dataset entry in a list (with R)
Right, I missed that part. You need to replace wrld_simpl[i, ] with wrld_simpl[s[i,"poly-id", ] or similar. Reproducible examples help, I'll try to make one for you if I get around to it.