search for: amvd

I cannot understand why xyplot does not work within a simple for loop. This works up to the for loop; inside the for loop the png files are opened and closed, but nothing is plotted. No error messages are written to the console either. This is the case on both Windows and Linux. By the way, running the script below on Linux using source() does not even produce the first xyplot. This is less of

I am choosing a file like this: #Bring up file selection box fn<-file.choose() fp<-file.path(fn,fsep='\\') Unfortunately, the file path contains the short file name and extension as well. I had hoped to get only the path so I could make my own long filenames (for output graphs) by concatenation with this file path. Of course I can split the string and assemble the components from

I have 8 cofactors possibly affecting one and only one variable. I make conditional histograms: <-pdf(file="tst3.pdf",paper="special",width=36,height=36) <-histogram(~Oversized|dat$c1*dat$c2*dat$c5*dat$c6*dat$c7*dat$c8*dat$c9*dat$c10,nint=21,layout=c(32,8),data=dat,type="count") <-dev.off() This works (compliments to R developers!) but it does generate a

I am trying to add 2 stdev error bars to lattice type plots: panel.ebar<-function(x,y,dy=NULL,...) { panel.xyplot(x,y,...) panel.segments(x,y-dy,x,y+dy,...) } Then: xyplot(y~x|fc,data=dat,dy=dat$dy,panel=panel.ebar) This adds error bars but they are not conditioned on the factor fc. xyplot(y+I(y-dy)+I(y+dy)~x|fc,data=dat) This produces 3 series of points in different colors, conditioned

I wonder whether R has methods for constrained fitting of linear models. I am trying fm<-lm(y~x+I(x^2), data=dat) which most of the time gives indeed the coefficients of an inverted parabola. I know in advance that it has to be an inverted parabola with the maximum constrained to positive (or zero) values of x. The help pages for lm do not contain any info on constrained fitting. Does anyone

I read records using scan: dat<-data.frame(scan(file="KDA.csv",what=list(t="%m/%d/%y %H:%M",f=0,p=0,d=0,o=0,s=0,a=0,l=0,c=0),skip=2,sep=",",nmax=np,flush=TRUE,na.strings=c("I/OTimeout","ArcOff-line"))) which results in: > dat[1:5,] t f p d o s a l c 1 1/21/09 5:01 16151 8.2 76 30 282 1060 53 7 2 1/21/09 5:02

I have timstamped data like this: > sd[1:10,] Tstamp Density Mesh50 Mesh70 Mesh100 Mesh150 Mesh200 2 2009/02/27 07:00 30.5 0.7 10.7 21.4 32.8 41.6 3 2009/02/27 08:00 32.2 1.6 12.4 23.3 34.5 43.0 4 2009/02/27 09:00 32.7 4.8 13.0 24.0 35.1 43.5 5 2009/02/27 10:00 26.7 0.3 6.5 17.6 28.1 36.9 6 2009/02/27 11:00

I use kmeans to classify spectral events in high and low 1/3 octave bands: #Do cluster analysis CyclA<-data.frame(LlowA,LhghA) CntrA<-matrix(c(0.9,0.8,0.8,0.75,0.65,0.65), nrow = 3, ncol=2, byrow=TRUE) ClstA<-kmeans(CyclA,centers=CntrA,nstart=50,algorithm="MacQueen") This works well when the actual data shows 1,2 or 3 groups that are not "too close" in a cross plot.

...elp me in the this regards. Thanks, Shreyasee     [[alternative HTML version deleted]] ------------------------------ Message: 2 Date: Wed, 27 May 2009 18:09:27 +0800 From: Berwin A Turlach <berwin@maths.uwa.edu.au> Subject: Re: [R] Constrained fits: y~a+b*x-c*x^2, with a,b,c >=0 To: amvds@xs4all.nl Cc: r-help@r-project.org Message-ID: <20090527180927.1814b009@berwin-nus1> Content-Type: text/plain; charset=US-ASCII G'day Alex, On Wed, 27 May 2009 11:51:39 +0200 Alex van der Spek <amvds@xs4all.nl> wrote: > I wonder whether R has methods for constrained fitting o...