[R] scatter plot of numerical variables against different sample ids

[Ivan Calandra]

Hi Maria,

What happens is that R plots with boxplots (explaining the horizontal 
lines, i.e. boxes with n=1) when the x-variable is a factor.
What you can do is transform your Sample column into numeric and then 
plot it, with some adjustment of axis labels.

For example:
datf <- data.frame(Sample=c("M1","M2","M3","M4","M5"), 
Cu=c(1,2.5,1.15,2,8), Zn=c(5,11,11,4,15), Mn=c(10,8,12,30,35))
datf$Sample2 <- as.numeric(datf$Sample)
with(datf, plot(Sample2, Cu, type="l", lty=1, col="red", xaxt="n"))
axis(1, at=datf$Sample2, labels=datf$Sample)

It might not be the easiest/best approach though... Someone here might 
have a better idea.

HTH,
Ivan

--
Ivan Calandra, PhD
MONREPOS Archaeological Research Centre and
Museum for Human Behavioural Evolution
Schloss Monrepos
56567 Neuwied, Germany
calandra at rgzm.de
+49 (0) 2631 9772-287
--
https://www.researchgate.net/profile/Ivan_Calandra
https://publons.com/author/705639/

Le 05/12/2016 à 13:25, Maria Lathouri via R-help a écrit :
> Dear all
> I know that my question is very simple but although I tried to find an answer online, I couldn't and I am stuck.
> I have a dataset of three numerical variables measured in different samples ID. Something like this:
> Sample        Cu        Zn        MnM1               1          5          10M2               2.5       11          8M3              1.15      11         12  M4                2         4          30M5                8        15         35
> I would like to plot these variables (Cu, Zn, Mn) (in y-axis) against the Sample ID (in x-axis) in a scatter plot with lines as I want to see how they change in the samples.
> I tried using the command>plot(Sample, Cu, type="l", lty=1, col="red")
> but I wouldn't get a line. Actually, I would get some small horizontal lines in each point. I tried to use type="p" but I would get the same thing.
> I would very much appreciate if you could help me on that. Apparently, I am missing something.
> Thank you in advance.
> Kind regards,Maria
> 	[[alternative HTML version deleted]]
>
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