'plot' is doing exactly what you are asking it to do. Take a close look at your data:
cyto_std_conc od [1,] 11.371777 10.00 [2,] 9.786814 8.00 [3,] 8.201852 6.00 [4,] 6.616889 4.00 [5,] 5.031927 2.00 [6,] 3.446964 1.00 [7,] 11.371777 10.50 [8,] 9.786814 7.80 [9,] 8.201852 6.40 [10,] 6.616889 3.80 [11,] 5.031927 2.10 [12,] 3.446964 0.95 > see between the 6th and 7th values you are asking it to draw a line from the lowest to highest. You want split your plotting into 'plot(data[1:6])' and lines(data[7:12]) to avoid the straight line. But should should away look at your data to see if that is what you intended. On Wed, Oct 20, 2010 at 11:18 AM, 1Rnwb <sbpuro...@gmail.com> wrote: > > Hello all, I am using 'plot' to create standard curves for elisa data. when I > use 'plot' with type='b' i get the points connected with lines and one > straigth line from the lowest datapoint to the highest data point. how can i > avoid/remove it from the figure. i am using R2.9.1, below is the example of > the data. > > od<-c(10, 8, 6,4,2,1, 10.5,7.8,6.4,3.8,2.1,0.95) > > cyto_conc=2650 # Highest cytokine concentration user > defined > > cyto_std_conc <-c(cyto_conc) > > for (i in 1:5) > { > cyto_conc = cyto_conc /3 > cyto_std_conc <-c(cyto_std_conc ,cyto_conc) > } > cyto_std_conc<-log2(rep(cyto_std_conc,2)) > cyto<-cbind(cyto_std_conc,od) > > plot(cyto_std_conc,od, type='b') > > I have searched help using '?plot' in R as well as google, all the examples > which are available online gives me the plot the way it is shown in the > example. but when i use the plot for my data it gives me a straight line. > thanks > sharad > -- > View this message in context: > http://r.789695.n4.nabble.com/Plot-creates-a-straigth-line-tp3004090p3004090.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > 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. > -- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve? ______________________________________________ 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.