On Aug 12, 2010, at 3:54 PM, TGS wrote:
Actually I spoke too soon David.
I'm looking for a function that will either tell me which point is
the intersection so that I'd be able to plot a point there.
Or, if I have to solve for the roots in the ways which were
demonstrated yesterday, then would I be able to specify what the
horizontal line is, for instance in the case where y (is-not) 0?
Isn't the abline h=0 represented mathematically by the equation y=0
and therefore you are solving just for the zeros of "f" (whaich are
the same as for (f-0)? If it were something more interesting, like
solving the intersection of two polynomials, you would be solving for
the zeros of the difference of the equations. Or maybe I have not
understood what you were requesting?
On Aug 12, 2010, at 12:47 PM, David Winsemius wrote:
On Aug 12, 2010, at 3:43 PM, TGS wrote:
I'd like to plot a point at the intersection of these two curves.
Thanks
x <- seq(.2, .3, by = .01)
f <- function(x){
x*cos(x)-2*x**2+3*x-1
}
plot(x,f(x), type = "l")
abline(h = 0)
Would this just be the uniroot strategy applied to "f"? You then
plot the x and y values with points()
David Winsemius, MD
West Hartford, CT
______________________________________________
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.
