Hi everyone,

I've searched a few R lists for an answer to this dilemma but it's got me stumped. I have a dataset not unlike the Puechabon dataset that's included with the Adehabitat package:

> data(puechabon)
> p = puechabon$locs
> p = p[-c(94:120,53:90,37:50,7:29),]
> p
    Name Age Sex      X       Y   Date
1  Brock   2   1 699889 3161559 930701
2  Brock   2   1 700046 3161541 930703
3  Brock   2   1 698840 3161033 930706
4  Brock   2   1 699809 3161496 930707
5  Brock   2   1 698627 3160941 930708
6  Brock   2   1 698719 3160989 930709
30 Brock   2   1 699207 3161099 930831
31 Calou   2   1 700098 3161648 930703
32 Calou   2   1 700310 3161323 930704
33 Calou   2   1 699877 3161471 930707
34 Calou   2   1 700003 3161360 930708
35 Calou   2   1 699820 3161387 930709
36 Calou   2   1 699778 3161328 930711
52  Chou   3   2 699640 3158702 920802
53  Chou   3   2 699689 3158857 920803
92  Jean   2   1 699448 3158689 930705
93  Jean   2   1 699500 3158684 930706
94  Jean   2   1 699409 3158794 930707

I'm trying to create an MCP for each animal that has 5 or more relocation points (e.g. Brock & Calou) and export each MCP to a CSV file. I've tried the following, but I get an error message:

> summary(p$Name)>=5
Brock Calou  Chou  Jean
 TRUE  TRUE FALSE FALSE

> for (i in 1:nrow(p)){
+ if(summary(p$Name)>=5){
+ mcp.p = mcp(pxy, pid, percent=95)
+ write.table(mcp.p, sep=",", file=paste(pid,".csv"), col.names=NA)
+ }
+ }
Error in mcp(pxy, pid, percent = 95) :
  At least 5 relocations are required to fit an home range
In addition: Warning message:
In if (summary(p$Name) >= 5) { :
  the condition has length > 1 and only the first element will be used

I'm not an expert in R and would appreciate any help.


Regards,

_________________________________
Hakim Abdi, M.Sc.
Research Intern

Conservation GIS/Remote Sensing Lab
Smithsonian Conservation Biology Institute
1500 Remount Road
Front Royal, VA 22630
phone: +1 540 635 6578
mobile: +1 747 224 7006
fax: +1 540 635 6506 (Attn:GIS Lab)
email: abdia@si.edu
http://nationalzoo.si.edu/SCBI/ConservationGIS/

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