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I would really appreciate it if someone can give suggestions on how to do spectra fitting in R using ordinary least square fitting and non-negativity constraints. The lm() function works well for ordinary least square fitting, but how to specify non-negativity constraints? It wouldn't make sense if the fitting coefficients coming out as negative in absorption spectra deconvolution. Thanks.

Thanks. Eric Leifer, Ph.D. Office of Biostatistics Research National Heart, Lung, and Blood Institute 6701 Rockledge Drive, MSC 8217 Bethesda, MD 20892-8217 Email: LeiferE@NHLBI.NIH.GOV Phone: 301-435-0436 FAX: 301-480-1862

I need to extract the p value from a ANOVA done with lm model fitting <- lm(var ~ group) Sfitting <- summary(fitting) Sfitting[10][1] gives the F value and the degrees of freedom but I am not able to get the p value. The function df should give a p value given a F but I am not able to make it work. I found only something about aov in the R help and I am not able to make it work Massimo

I am not able to compile R under ubuntu Edgy. ./configure error message is configure: error: --with-x=yes (default) and X11 headers/libs are not available I do not know which library is missing (I tried to install some X11 libs but were already on the system). Massimo Cressoni

I am writing some code to obtain publication-like plots (like the ones can be obtained with SigmaPlot). I am not able to find the dimensions of a point. Parameters like cex make you able to make it bigger or smaller but I need to know the exact dimension (in relative coordinates : if my plot is 640x480 a dot plotted with cex=1.5 will be...) Massimo Cressoni

I am trying to write a function that fits a sigmoid given a X and Y vector guessing the start parameters. I use nls. What I did (enclosed) seems to work well with many data points but if I want to fit small vectors like : pressure <- c(5,15,9,35,45) gas <- c(1000,2000,3000,4000,5000) it do not work. The help page says that it do no not work on zero residual data. Massimo Cressoni

I know that this maybe a trivial question. I am not able to plot pedices in graph axes. Instead I am able to plot different math symbols : XLABEL <- expression(paste(cmH,lim(f(x), x %->% 0),"O PEEP")) works well XLABEL <- expression(paste(cmH,[2],"O PEEP")) is considered a wrong expression. Thanks

I need to perform the Exact Wilcoxon Mann-Whitney on a subset of my database. Assuming that IPPO is my data frame and IPPOBIS is the subset my variable still have 3 different levels and the function wilcox_test (package "coin") does not accept it. I do not know how to overcome this problem. ippo <- c(rep("A",10),rep("B",10),rep("C",10)) ippo2 <-

...llaboration with the laboratory of Dr. Ellen Rothenberg (Caltech), with code contributions by SparkTech Software, and Bioconductor contributions by Dr. Martin Morgan of the Fred Hutchinson Cancer Research Center. The development of this free, open-source community resource was supported in part by NHLBI grant number HL089102 to Hamid Bolouri. The CRdata Development Team (http://crdata.org/about)

...I'll see if my support staff here at the National Institutes of Health have any suggestions. Thanks again, Eric -----Original Message----- From: Friedrich.Leisch@tuwien.ac.at [mailto:Friedrich.Leisch@tuwien.ac.at] Sent: Friday, April 29, 2005 11:44 AM To: Peter Dalgaard Cc: Leifer, Eric (NIH/NHLBI); r-devel@stat.math.ethz.ch Subject: Re: [Rd] I'm unable to download R from any of the CRAN mirrors. Any sugge (PR#7823) >>>>> On 29 Apr 2005 17:29:43 +0200, >>>>> Peter Dalgaard (PD) wrote: > This is not a bug in R. Please do not misuse the bug repository....

During the installation I do my './configure' but the 'make' command does not work. I'm using the Sun native make, full path /usr/xpg4/bin/make and we have a gcc compiler. I could really use some help trying to understand what the make com- mand is doing. (or not doing in my case) George ===================== George Caunt Systems Administrator Framingham Heart Study 73