[R] How to refer a variable in quotes

[Jim Lemon]

Hi Jinggaofu,
Try this:

for(u in 1:9) {
 pdffile<-paste(g[u],".pdf",sep="")
 pdf(pdffile)
...
mtext(g[u],side=4)

If you index the vector g, it will return one or more character strings.

Jim


On Thu, Mar 3, 2016 at 9:52 AM, Jinggaofu Shi <js3786 at drexel.edu> wrote:
> Hi, there
> I am new to R, here is an urgent question.
> I want to save several graphs by a for loop. But I don't know how to refer
> the variable in the quotes.
> Here is my code.
>
> g<-c("g1","g2","g3","g4","g5","g6","g7","g8","g9")
> for (u in 1:9) {pdf("g[u]".pdf")
> + plot(1,1, xlim=range(x), ylim=c(-5,5), type='n', xlab ="Femur length
> (mm)", ylab = "Z-Score")
> + mtext("g[u]", side = 4)
> + for (i in z) {
> + lines(x,(log(i)-(m[u]*log(x)+c[u]))/r[u])
> + miny<-(log(i)-(m[u]*log(max(x))+c[u]))/r[u]
> + maxx <- exp((log(i)-c[u]+5*r[u])/m[u]);
> + if (miny > -5) {text(max(x),miny+0.3,i)
> + }else {text(maxx+2, -5+0.3,i)}
> +  }
> + dev.off()
> + }
>
> In the second line, I want to refer the variable 'g[n]' to the file name
> and fifth line i also want to refer the variable as a note. How should I
> do? Thank you very much!
>
> --
> Sincerely,
> Jinggaofu Shi
> 4029 Spring Garden Street
> Philadelphia, PA 19104
> Email: shijinggaofu at gmail.com
> Phone: 215-847-9145
>
>         [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.