Just 'cos it's bent doesn't mean you need nls. With your data, lm fits (suspicously!) well...
y<-c(0.000,0.004,0.008,0.016,0.024,0.032,0.044,0.064,0.072,0.088,0.108,0.140 ,0.156,0.180,0.208,0.236,0.264,0.296,0.320,0.360,0.408,0.444,0.472,0.524 ,0.576) x<-c(100,200,300,400,500,600,700,800,900,1000,1100,1200,1300,1400,1500 ,1600,1700,1800,1900,2000,2100,2200,2300,2400,2500) plot(x,y) lines(x, predict(lm(y~I(x^2)))) >>> "Nathan S. Watson-Haigh" <nathan.watson-ha...@csiro.au> 01/12/09 2:19 AM >>> -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I have the following data: > y [1] 0.000 0.004 0.008 0.016 0.024 0.032 0.044 0.064 0.072 0.088 0.108 0.140 [13] 0.156 0.180 0.208 0.236 0.264 0.296 0.320 0.360 0.408 0.444 0.472 0.524 [25] 0.576 > x [1] 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 [16] 1600 1700 1800 1900 2000 2100 2200 2300 2400 2500 I'd like to plot the points and calculate a curved line of best fit. I know I need to use nls(), but I'm unsure how to begin....any pointers? Cheers, Nathan - -- - -------------------------------------------------------- Dr. Nathan S. Watson-Haigh OCE Post Doctoral Fellow CSIRO Livestock Industries Queensland Bioscience Precinct St Lucia, QLD 4067 Australia Tel: +61 (0)7 3214 2922 Fax: +61 (0)7 3214 2900 Web: http://www.csiro.au/people/Nathan.Watson-Haigh.html - -------------------------------------------------------- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAklqqJsACgkQ9gTv6QYzVL4gCgCgy4qShoFX/9QWgKsBqHPhLCDS r+AAnRD3kbkImG3rVaBN6d4BP2cUmqYZ =yVLj -----END PGP SIGNATURE----- ______________________________________________ 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. ******************************************************************* This email and any attachments are confidential. Any use...{{dropped:8}} ______________________________________________ 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.
