Le samedi 28 mars 2009 à 16:06 +0000, Wanja Mathar a écrit :
> Hi everyone,
>
> i have a matrix of points and want to calculate the direction and length of
> each vector between the points.
>
> I can easily calculate the length with dist(testdata), but is their a
> function that returns a matrix of the direction of the vectors between points
> (angles 0-360°)?
>
> testdata <- matrix(1:8, nrow=4, ncol=2,
> dimnames=list(c("A","B","C","D"), c("x","y"))
?atan2 ; ?outer
Emmanuel Charpentier
______________________________________________
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.
