Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

Thank you Robert, I amended my previous post to correct the duplicate use of the x variable and to provide an intuitive black to white color ramp for the ice. - Tony Fischbach, Wildlife Biologist Walrus Research Program Alaska Science Center U.S. Geological Survey 4210 University Drive Anchora

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

Tony, On Wed, Oct 19, 2011 at 1:13 PM, Anthony Fischbach wrote: > This works beautifully. > Is there a trick to applying an intuitive color ramp to the png file You can provide a list of colors such as that generated by rainbow , heat.colors

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

cron on Linux systems. Tom - Original Message - From: Anthony Fischbach Date: Wednesday, October 19, 2011 2:04 pm Subject: Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files To: r-sig-geo@r-project.org > Thank you for the GRASS suggestion. > It wo

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

This works beautifully. Is there a trick to applying an intuitive color ramp to the png file and setting the non-ice to null values? I have tried to assign all non ice and ice = 0 values to NA. This works down to the level of the extract function. ... fileName <- 'ftp://sidads.colorado.edu/pub/DA

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

Anthony, projectRaster failed because it uses projectExtent, which fails to give the right answer for a circumpolar dataset. I used projectExtent to make projectRaster more efficient. I took it out and now things work as expected on these data (and perhaps a bit slower in some other cases). Fixed

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

Not sure what's going on here, I need to investigate. But this work-around, which replicates the essence of projectRaster works for me: library(rgdal) x <- raster(ymn=60) res(x) <- 0.25 xy <- coordinates(x, sp=T) xypole <- spTransform(xy, projection(r, asText=F)) x[] <- extract(r, xypole, method=

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

On Wed, 19 Oct 2011, Anthony Fischbach wrote: Thank you for the GRASS suggestion. It would also be straight forward in ArgGIS, but I seek to run this all in a scripting environment with the full flexibility of R such that I may automate the whole process. I have a feeling that this is strandin

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

Thank you for the GRASS suggestion. It would also be straight forward in ArgGIS, but I seek to run this all in a scripting environment with the full flexibility of R such that I may automate the whole process. Following on the projectRaster idea, I have tried using the from and to options, first c

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

Tony, This would be a far easier task in, say, GRASS GIS — once the data is there, R integrates very nicely with GRASS, making the combination quite powerful. Tom On 10/19/11 1:36 PM, Anthony Fischbach wrote: Very elegant! But the projection seems to have trouble. Please see images of the

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

Very elegant! But the projection seems to have trouble. Please see images of the original raster and the projected raster produced with plot commands. http://r-sig-geo.2731867.n2.nabble.com/file/n6909694/rr.png http://r-sig-geo.2731867.n2.nabble.com/file/n6909694/rgeo.png - Tony Fischbach,

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

Here is one approach: rgeo <- projectRaster(rr, crs="+proj=longlat +datum=WGS84") KML(rgeo, "file.kml") Best, Robert On Wed, Oct 19, 2011 at 10:00 AM, Anthony Fischbach wrote: > In my previous post I happily handled the binary National Snow and Ice Data > Center sea ice imagery and cast it int

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

In my previous post I happily handled the binary National Snow and Ice Data Center sea ice imagery and cast it into a GeoTiff. My next challenge is to wrap the GeoTiff into a kml overlay. Continuing the code from the previous post, I pick it up just after writing the raster object to the geoTiff.

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

This works: http://r-sig-geo.2731867.n2.nabble.com/file/n6890251/test.png require(sp) library(raster) library(rgdal) pixel <- 25000 #pixel dimension in meters for both x and y xMin <- -3837500 #From NSIDC: ulxmap -3837500 xMax <- xMin + (pixel*304) yMax <- 5837500 #From NSIDC: ulymap 5837500 yM

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

in 1:304){ >x <- as.integer(readBin(bincon,"raw",1)) >if(x<251) result[i,j]<- x/250 >} >} >close(bincon) >image(result) > } > > >From here I would need to build t

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

.. Tony Fischbach, Wildlife Biologist Walrus Research Program Alaska Science Center U.S. Geological Survey 4210 University Drive Anchorage, AK 99508-4650 Phone: 907 786-7145 FAX: 907 786-7150 afischb...@usgs.gov http://alaska.usgs.gov/science/biology/walrus From: Barry Rowlingson To: Mi

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

VRT is not designed to interrogate raw files, it's for arbitrarily specifying a raster sources from a variety of sources, including "raw" - there would be a driver and auto-recognition forze the files if GDAL knew about it. The 300 byte header is describe here so there's a nice little project for

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

On Wed, Oct 12, 2011 at 11:08 AM, Barry Rowlingson wrote: >  Annoyingly I don't think gdal's raw data vrt system can find out the > number of pixels across/down the raster - you have to code them into > the .vrt file. I reckon with a bit of unix (or in extremis, C code) > craftiness it would be p

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

On Wed, Oct 12, 2011 at 12:14 AM, Michael Sumner wrote: > Doing it manually is straightforward but laborious and error-prone, > another option is to use the GDAL VRT format - where you can formalize > all of the data type, georeferencing, projection and other metadata > (scaling and so on if nece

Re: [R-sig-Geo] Reading National Snow and Ice Data Center binary files

Since the format is raw binary it would be easy enough to read the raw values with ?readBin and construct a Spatial object from that. If there is sufficient metadata with the files it might already be recognized by a GDAL, and if you are lucky in turn by your build of rgdal (I've not checked the fi

[R-sig-Geo] Reading National Snow and Ice Data Center binary files

Has anyone developed scripts for converting the National Snow and Ice Data Center binary files to spatial pixel data frames? The data format is described under http://nsidc.org/data/docs/daac/nsidc0081_ssmi_nrt_seaice.gd.html#format - Tony Fischbach, Wildlife Biologist Walrus Research Program