Hi,
plot(xc, yc, type="l", ylim=c(0,50), xlim=c(0,50), lwd=2, xlab="M", ylab="seconds") abline(a=-think, b=cpustime, lty="dashed", col="red") abline( 2.2, 0, lty="dashed", col = "red") This draws a response time curve an asymptote and a horizontal line. How do I draw a line from the intersection of the asymptote and the horizontal to intersect the y-axis ? I also want to calculate the value at this y-axis intersection point. Thanks, Mohan DISCLAIMER:\ ===============...{{dropped:31}} ______________________________________________ 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.