On Wed, 15 Jun 2016 at 18:51 Rolf Turner <r.tur...@auckland.ac.nz> wrote:
> On 15/06/16 20:18, Jim Lemon wrote: > > Hi Alice, > > Have you tried creating a vector of the start position (xpos[1],ypos[1]): > > > > xstart<-rep(xpos[1],n) > > ystart<-rep(ypos[1],n) > > # where "n" is the number of subsequent positions in the trip > > max(trackDistance(xstart,ystart,xpos[2:n],ypos[2:n],...)) > > > > may then give you the value of the longest distance from the start. I > > don't have the trip package or I could see if you really need to > > replicate the start positions. > > Jim: This seems to me to be somewhat off the point. The OP was faced > with the problem of not being able to access the function homedist(). > This function seems *not* to be exported from the trip package, and yet > it is a *documented* function which I would assume to imply that users > should be able to invoke it directly. > > It is possible that in the past the OP was dealing with a version of the > trip package that was created before namespaces came into the picture, > whence "exporting" was not relevant. I would suggest that the OP > contact the package maintainer (maintainer("trip") will give you the > email address) and enquire as to what is going on. > > This is correct, the maintainer of trip never finished the task and so it's documented but not exported - but also the CRAN version is incorrect so please don't use it. Apologies for this. > In the interim, a workaround *might* be to invoke homedist() as > > trip:::homedist(<whatever>) > Please don't do this, the current definition is incorrect. I've updated it here but can't spend much time checking, any direct input to me is welcome - perhaps via the Issues feature on the GitHub repository. https://github.com/mdsumner/trip Again, my apologies for this. Cheers, Mike. > Note the *triple* colon in the foregoing. I am not at all familiar with > the trip package so my advice should probably be taken with several > grains of salt. > > cheers, > > Rolf Turner > > -- > Technical Editor ANZJS > Department of Statistics > University of Auckland > Phone: +64-9-373-7599 ext. 88276 > > > On Wed, Jun 15, 2016 at 1:43 PM, Alice Domalik <adoma...@sfu.ca> wrote: > >> Hi List, > >> > >> I'm relatively new to R, so apologies if my question is rather > elementary. > >> I'm working with some bird tracking data and I would like to calculate > the maximum distance traveled from the colony. > >> For the maximum distance traveled, I was going to use the function > homedist(). However, when I try to use this function I get the following > error: > >> Error: could not find function "homedist" > >> Anyone know why I would get this error? I have been using other > functions in "trip" without an issue. Is there an alternative way I can > calculate this? > >> > >> Thanks in advance for any help! > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. > -- Dr. Michael Sumner Software and Database Engineer Australian Antarctic Division 203 Channel Highway Kingston Tasmania 7050 Australia [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.