I've really been on a roll this week; the formula for the lines that I presented was completely wrong.
But I'm glad I learned about mapply. I used this: mapply(abline, (converge$kY + tan((90-converge$kT) * pi / 180)*(-converge$kX)), tan((90-converge$kT) * pi / 180)) Tom! On Thu, Apr 2, 2009 at 8:29 AM, r...@quantide.com <r...@quantide.com> wrote: > May be: > > plot(c(-1, 1) , c(-1, 1), type = "n") > n = 4 > a = rep(0, n) > b = 1:n/n > > > fun = function(i, a, b, col = 1 , ...) { > abline(a[i], b[i], col = col[i], ...) > } > > lapply(1:n, fun, a=a, b=b, col = 1:n) > > Andrea > > > Thomas Levine wrote: > >> I really want to do this: >> >> abline( >> a=tan(-kT*pi/180), >> b=kY-tan(-kT*pi/180)*kX >> ) >> >> where kX,kY and kT are vectors of equal length. But I can't do that >> with abline unless I use a loop, and I haven't figured out the least >> unelegant way of writing the loop yet. So is there a way to do this >> without a loop? >> >> Or if I am to resort to the loop, what's the best way of doing it >> considering that I have some missing data? Here's the mess that I >> wrote. >> >> converge <- na.omit(data.frame(kX,kY,kT)) >> for (z in (length(converge$kT))) >> {abline( >> a=tan(converge$kT[z]*pi/180), >> b=converge$kY[z]-tan(-converge$kT[z]*converge$kX[z]*pi/180) >> )} >> >> I think the missing data are causing the problem; this happens when I run: >> >> Error in int_abline(a = a, b = b, h = h, v = v, untf = untf, ...) : >> 'a' and 'b' must be finite >> >> ______________________________________________ >> 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. >> >> >> > > [[alternative HTML version deleted]] ______________________________________________ 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.