On Jun 25, 2009, at 1:51 PM, Ted Harding wrote:
On 25-Jun-09 18:38:37, Marc Schwartz wrote:
On Jun 25, 2009, at 1:30 PM, Lesandro wrote:
Hello all,
How to draw a line in plot when I know the start point(x1,y1)
and end point(x2,y2)? I need make this as additional information
in the graph:
plot(wl2[[1]],wl2[[2]])
I think that is possible make this with the function abline(), is
possible? I looked the function lines() too, but don't understand
as make.
Thanks!
Lesandro
See ?segments which does just what you are looking for.
lines() is more designed for a series of connected lines (eg. a
polygon) rather than a single line segment.
abline() can draw a straight line, at a given vertical or horizontal
position, or if given a linear model object, the fitted line.
HTH,
Marc Schwartz
Hmm ... for this particular purpose I don't see what is wrong with
plot(wl2[[1]],wl2[[2]])
lines(c(x1,x2),c(y1,y2))
along with any additional paramaters to lines() for line-type,
colour, etc. -- I do this all the time ...
Ted.
Nothing wrong at all Ted. It will of course work.
For example:
plot(1:10)
lines(c(2, 4), c(6, 8))
That will give you the same result as:
plot(1:10)
segments(2, 6, 4, 8)
In this case, it may be a matter of choice. For single lines, I tend
to use segments().
As is frequently the case with R, there is more than one way to skin
the feline...
Regards,
Marc
______________________________________________
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.
