[R-sig-Geo] histogram of SpatialGridDataFrame values

[Michael Sumner]

More simply perhaps you can get any column by name or number like any
data.frame - this gives all pixel values for the first attribute
(assuming first colname is the default - use names(dem) to find out):

dem$band1

dem[[1]]



On Fri, Aug 5, 2011 at 12:04 PM, Nick Matzke <matzke at berkeley.edu> wrote:
> Nevermind, got it: as.matrix(dem)
>
> On 8/4/11 5:06 PM, Nick Matzke wrote:
>>
>> Hi,
>>
>> So I've loaded a DEM into a SpatialGridDataFrame, and I can
>> plot it etc.
>>
>> However, I would like to make a histogram of the pixel
>> values (or just a random sample of the pixel values) to help
>> make decisions about the color scheme etc. Is there an easy
>> way to do this?
>>
>> Cheers!
>> Nick
>>
>>
>
> --
> ====================================================
> Nicholas J. Matzke
> Ph.D. Candidate, Graduate Student Researcher
>
> Huelsenbeck Lab
> Center for Theoretical Evolutionary Genomics
> 4151 VLSB (Valley Life Sciences Building)
> Department of Integrative Biology
> University of California, Berkeley
>
> Graduate Student Instructor, IB200B
> Principles of Phylogenetics: Ecology and Evolution
> http://ib.berkeley.edu/courses/ib200b/
> http://phylo.wikidot.com/
>
>
> Lab websites:
> http://ib.berkeley.edu/people/lab_detail.php?lab=54
> http://fisher.berkeley.edu/cteg/hlab.html
> Dept. personal page:
> http://ib.berkeley.edu/people/students/person_detail.php?person=370
> Lab personal page: http://fisher.berkeley.edu/cteg/members/matzke.html
> Lab phone: 510-643-6299
> Dept. fax: 510-643-6264
>
> Cell phone: 510-301-0179
> Email: matzke at berkeley.edu
>
> Mailing address:
> Department of Integrative Biology
> 3060 VLSB #3140
> Berkeley, CA 94720-3140
>
> -----------------------------------------------------
> "[W]hen people thought the earth was flat, they were wrong. When people
> thought the earth was spherical, they were wrong. But if you think that
> thinking the earth is spherical is just as wrong as thinking the earth is
> flat, then your view is wronger than both of them put together."
>
> Isaac Asimov (1989). "The Relativity of Wrong." The Skeptical Inquirer,
> 14(1), 35-44. Fall 1989.
> http://chem.tufts.edu/AnswersInScience/RelativityofWrong.htm
>
> _______________________________________________
> R-sig-Geo mailing list
> R-sig-Geo at r-project.org
> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>



-- 
Michael Sumner
Institute for Marine and Antarctic Studies, University of Tasmania
Hobart, Australia
e-mail: mdsumner at gmail.com