[R] data extraction in R

2012-01-24 Thread crimsonengineer87
All, I currently have a dataset with a variety of different columns, let's say, A,B,C, and D. I'd like to run an R script that graphs only certain rows of the dataset based on what's in column A. In awk, it'd be something like: awk ' { if(A==5 && B ==6) print $0 } ' datafile | command or file Si

Re: [R] breakpoints and nonlinear regression

2012-01-18 Thread crimsonengineer87
Thanks for the comments. Yes, I also had segmented and then I went away from that. I can't remember. I've tried using it but I get some sort of strange error. Here's some code ... pavlu.glm <- glm(Na ~ yield, data=pavludata, family=gaussian) pavlu.seg <- segmented(pavlu.glm, seg.Z=~yield, psi=100

Re: [R] breakpoints and nonlinear regression

2012-01-17 Thread crimsonengineer87
Thanks for the comments everyone. I was hoping to not have to find someone in the stats department ... well, we'll see. So in response to Z's comment ... I have tried breakpoints(Na ~ yield) and I did expect to get something continuous. The idea was to get two or three linear functions making up t

Re: [R] breakpoints and nonlinear regression

2012-01-17 Thread crimsonengineer87
Hi Ken, Thx for that advice. I took a brief look at it. I already have my curve by just using the curve() function using the parameters a and b given by the nls. Would se.fit and interval have computed the CI? Maybe where I'm confused is at how I can break up my curve into pieces of linear regres

[R] breakpoints and nonlinear regression

2012-01-17 Thread crimsonengineer87
Dear Forum, I have been wracking my head over this problem for the past few days. I have a dataset of (x,y). I have been able to obtain a nonlinear regression line using nls. However, we would like to do some statistical analysis. I would like to obtain a confidence interval for the curve. We thou