Hello R-users, I am a biginner in R and I would like to fit a sinusoidal curve to my data. I couldn't get a nice results.
here is an extract of my data: line time meters 1 1 04:27 3.1 2 2 10:48 0.9 3 3 16:49 2.9 4 4 23:00 1.0 5 5 05:03 3.1 6 6 11:29 1.0 7 7 17:26 2.8 8 8 23:42 1.1 9 9 05:42 3.0 10 10 12:14 1.1 11 11 18:09 2.7 12 12 00:31 1.2 the time is in hours. I have tried to run this scrip trying to fit my data by eye using a time every 6 hours (just to try with a fixed time) TimeD <- c(0,6,12,18,24) MetersD <- c(3.1,0.9,2.9,1,3.1) AverageHigh <- (max(MetersD) + mean(MetersD)) / 2 AverageLow <- (min(MetersD) + mean(MetersD)) / 2 A <- (AverageHigh - AverageLow) / 2 K <- (AverageHigh + AverageLow) / 2 period <- mean(TimeD[c(-1,-2,-length(TimeD)-1,-length(TimeD))]) f <- 2 * pi / period phi <- TimeD[2] + (pi / (2 * f)) Curve.plot <-(A * sin(f * (TimeD - phi))) + K could somebody suggest me a way?It is becoming very complicated to get out from here. Many thanks ______________________________________________ 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.