r <-(structure(list(TSS = c(2.8, 8.4, 11, 1.3, 4.2, 2, 3.4, 14, 8.2, 3.1, 1.4, 0.9, 0.5, 6.1, 9.2, 0.6, 1, 11, 2.4, 1.2, 1.3, 1.3, 0, 1.8, 8, 11, 11, 8.5, 8.5, 1.8, 13, 4.4, 1.4, 2.1, 0.5, 25, 25, 9.3, 6.1, 1.6, 1.5, 19, 19, 24, 9.6, 1.8, 1.4, 1), GPP = c(1.213695235, 3.817313822, 1.267930498, 10.45692825, 3.268295623, 3.505286001, 4.468225245, 0.915653726, 1.635617261, 3.726133898, 1.363453706, 13.99650967, 1.581182762, 0.417618143, 0.741080504, 1.366790205, 0.969326797, 0.412440872, 1.780215366, 3.515743675, 8.248491445, 0.125726306, 13.95880794, 4.850627229, -0.438311644, 1.537773727, 1.537773727, 3.249103284, 3.249103284, 2.470317011, 0.768531626, 2.633107621, 3.113199095, 0.773824094, 3.208461305, 0.680150068, 0.680150068, 0.026385752, 0.369310858, 8.049276658, 7.487378383, 0.950072035, 0.950072035, 0.763580377, 0.333244629, 5.475999014, 9.235631398, 2.587682905), RiverMile = c(148L, 179L, 185L, 202L, 179L, 185L, 190L, 119L, 148L, 179L, 185L, 202L, 215L, 119L, 202L, 198L, 215L, 148L, 198L, 190L, 202L, 215L, 198L, 198L, 215L, 148L, 148L, 202L, 202L, 215L, 119L, 179L, 185L, 190L, 198L, 61L, 61L, 119L, 148L, 202L, 202L, 61L, 61L, 119L, 148L, 185L, 202L, 215L )), .Names = c("TSS", "GPP", "RiverMile"), class = "data.frame", row.names = c(12L, 13L, 14L, 19L, 25L, 26L, 28L, 34L, 35L, 36L, 37L, 42L, 44L, 58L, 75L, 85L, 88L, 91L, 97L, 107L, 142L, 144L, 155L, 166L, 169L, 185L, 186L, 201L, 202L, 207L, 219L, 221L, 222L, 224L, 226L, 230L, 231L, 250L, 251L, 258L, 283L, 287L, 288L, 303L, 304L, 306L, 311L, 313L)))
library(lattice) library(ggplot2) z <- nls(GPP~(a/(TSS+b)), start=c(a=0.01, b=0.01), data=r) f <- seq(-1, 29, length=100) y <- coef(z)["a"]/(f+coef(z)["b"]) pred <- data.frame(GPP = f, TSS = y) #this is what I can do qplot(TSS, GPP, data=r, colour=as.factor(RiverMile)) + geom_line(data=pred, colour ="black") #I would like to do this and then add the nls line qplot(TSS, GPP, data=r, shape=as.factor(RiverMile))+scale_shape_manual(values=1:9) #how do you undo the mapping of shape to add a line is my question #thanks -- Stephen Sefick Research Scientist Southeastern Natural Sciences Academy Let's not spend our time and resources thinking about things that are so little or so large that all they really do for us is puff us up and make us feel like gods. We are mammals, and have not exhausted the annoying little problems of being mammals. -K. Mullis ______________________________________________ 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.