Hi all, I am doing some basic regression analysis, and am getting a bit confused on how to enter non-polynomial formulas to be used.
For example, consider that I want to find A and r such that the formula y = A*exp(r*x) provides the the best fit to the line y=x on the interval [0,50]. I can set: xpts <- seq(0, 50, by=0.1) ypts <- seq(0, 50, by=0.1) I know I can find a fitted polynomial of a given degree using lm(ypts ~ poly(xpts, degree=5, raw=TRUE)) But am confused on what the formula should be for trying to find a fit to y = A*exp(r*x). If anyone knows of a resource that describes the "grammar" behind assembling these formulas, I would really appreciate being pointed in that direction as I can't seem to find much beyond basic polynomials. Thanks for the help! ______________________________________________ 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.
