[R-sig-eco] Adehabitat NMs Error

carmoms carmoms at uevora.pt
Fri Feb 6 18:45:11 CET 2015


Hello,

I’m trying to calculate Null Models for Animal Movement Analysis using 
adehabitatLT, but each time I try to constrain the random movements an 
error occurs.
So the codes I use are:
# Transform my locations points in ltraj
daho025<-as.character(Loc_025$DataHora)
head(daho025)
[1] "19-04-201200:56" "19-04-201201:35" "19-04-201205:48" 
"19-04-201206:30" "19-04-201220:09" "19-04-201220:48"
daho1025 <- 
as.POSIXct(strptime(as.character(Loc_025$DataHora),"%d-%m-%Y%H:%M"))
head(daho1025)
[1] "2012-04-19 00:56:00 BST" "2012-04-19 01:35:00 BST" "2012-04-19 
05:48:00 BST" "2012-04-19 06:30:00 BST" "2012-04-19 20:09:00 BST" 
"2012-04-19 20:48:00 BST"
Apo025 <- as.ltraj(xy = Loc_025[,c("X_WGS84","Y_WGS84")],
	date = daho1025, id = Loc_025$Codigo_ind)

# Transform my raster in to SpatialPixelsDataFrame:
PatTalSPDF<-as(PatTal, "SpatialPixelsDataFrame")

# To calculate the random walks:
# my function
myfunc <- function(x, par)
{par(mar = c(0,0,0,0))
image(par)
lines(x[,1], x[,2], lwd=2)}

# constrain function
consfun <- function(x, par)
{coordinates(x) <- x[,1:2]
ov <- over(x, geometry(PatTalSPDF))
return(all(!is.na(ov)))}

rxy <- apply(coordinates(S),2,range)
rxy
nmo2 <- NMs.randomShiftRotation(na.omit(Apo025), rshift = TRUE, rrot = 
TRUE,rx = rxy[,1], ry = rxy[,2], treatment.func = myfunc, treatment.par 
= PatTalSPDF, constraint.func=consfun, constraint.par=PatTalSPDF, 
nrep=9)


The result is always:
Error : identicalCRS(x, y) is not TRUE
Error in FUN(1L[[1L]], ...) :
   The constraint function fails for animal 1 :
it should work at least for all observed trajectories

I used the same function with the example in the package reference 
manual and it worked. Can anyone help me?

Thank you for your time.

Best wishes,

Carmo Silva



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