Hello, I've found the function isPeak from the Bioconductor package "PROCess" very useful for peak finding. My data was similar to yours (spectroscopy, i'm a physicist) but not time dependent. It may be a starting point to work on one spectrum, retrieve a few relevant informations (peak positions, widths, intensities,...), and process similarly at regular time intervals.
< www.bioconductor.org/packages/2.0/ bioc/vignettes/PROcess/inst/doc/ howtoprocess.pdf > hope this helps, baptiste On 17 Apr 2008, at 02:26, Bryan Hanson wrote: > Hi Folks... No code to troubleshoot here. I need some suggestions > about the > right terminology to use in further searching, and any suggestions > about R > pkgs that might be appropriate. > > I am in the planning stages of a project in which IR, NMR and other > spectra > (I'm a chemist) would be collected on various samples, and individual > samples would be followed over time. The spectra will be feature > rich/complex, so one can't see the changes by visual inspection. The > spectra are basically 2D matrices: peaks as a function of > frequencies. So > the data set is in the form of spectra of a single sample over > time, for > multiple samples. > > I am wondering about methods & R pkgs that can be used to analyze > changes in > the spectra over time. For instance, I would like to find specific > peaks > that are changing over time, sets of peaks that are changing in a > correlated > way over time etc. I'd like to do this in an efficient and > statistically > valid way. What I am thinking of is somewhat like a time series, > somewhat > like image analysis (but only 2D), but it's not quite either of > those and I > need to know what it's really called to investigate further. > > Any suggestions as to R pkgs and key words/phrases will be > appreciated. > > TIA, Bryan > ************* > Bryan Hanson > Professor of Chemistry & Biochemistry > DePauw University, Greencastle Indiana USA > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting- > guide.html > and provide commented, minimal, self-contained, reproducible code. _____________________________ Baptiste Auguié Physics Department University of Exeter Stocker Road, Exeter, Devon, EX4 4QL, UK Phone: +44 1392 264187 http://newton.ex.ac.uk/research/emag http://projects.ex.ac.uk/atto ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
