R help - Dec 2011 - Error message: object 'A' not found

I ran the following code:

And I run into problems with the last line of code (when it says
hn<-......).  I keep getting an error code: Error in distsamp(~hab ~ 1,
peldist, keyfun = "halfnorm", output = "density",  : 
  object 'A' not found


I would appreciate any and all help.  



rm(list=ls(all=TRUE))                                  #clear the computer's
memory of variables

setwd("E:\\Analysis")
# Part 1
library(unmarked)                                      # this loads the
'unmarked' package in R
Pellet <- read.table("PelletDistance.csv", sep=",",
header=T)  # read in the
data
head(Pellet)                                           # this provides a
header of the first few lines of data and variable names
Treatment <- Pellet[66:166,]                                  # Isolates
data for just the good habitat
Control <- Pellet[1:65,]                                 # same for bad
habitat
hist(Pellet$Distance,freq=F,xlim=c(0,7))             # plots a histogram, or
frequency distribution of the data


# Part 2
# Create formated distance response matrix
cp <- c(0,0.50,2,3.50,5.00,6.50)                         # Distance cut
points defining distance intervals
yDat <- formatDistData(Pellet, "Distance", "Line", cp) #
This creates a
formatted data matrix for number of observations at each distance interval
for each transect
yDat
# Prepare habitat covariates for each transect based on the stratum they
reside in
hab <-
matrix(c("C","C","C","C","C","C","C","C","C","T","T","T","T","T","T","T","T","T"),nrow=18,ncol=1)
#CHANGE THIS!!! nrow=# of T and Cs or A-Ks (same #)
hab <- data.frame(hab)

#Year effects
year <-
matrix(c("Year1","Year1","Year1","Year1","Year2","Year2","Year2","Year2","Year2","Year1","Year1","Year1","Year1","Year2","Year2","Year2","Year2","Year2"),nrow=18,ncol=1)
#CHANGE THIS!!! to match number of A-Ks And change nrow
year <- data.frame(year)


# Prepare transect lengths
len <-
as.numeric(c(100,100,100,100,100,100,100,100,100,100,100,100,100,100,100,100,100,100))
#Make this equal A, AA....KK for number of 10000s 

# Organize distance data along with covariates and metadata, MAKE SURE THESE
COVARIATES ARE RIGHT, MAYBE I CAN ADD MINE HERE
peldist <- unmarkedFrameDS(y=yDat, siteCovs = data.frame(hab, year),
dist.breaks=cp, tlength=len, survey="Line", unitsIn="m")
peldist                                                # look at the data
summary(peldist)                                       # get a summary of
the data

# Part 3
# Fit models without covariates
hn <- distsamp(~1 ~1, peldist, keyfun="halfnorm",
output="density",
unitsOut="ha")

--
View this message in context:
http://r.789695.n4.nabble.com/Error-message-object-A-not-found-tp4140237p4140237.html
Sent from the R help mailing list archive at Nabble.com.