[R-sig-eco] Issue with ltraj function in R for movement analysis

[alittle]

I'm currently working on an first-passage time analysis under the
adehabitatLT package. To begin, I'm trying to bring my data into R and run a
simple set of movement metrics output by the ltraj function. My data
consists of individual animal IDs, date, time, and x,y coordinates. I
followed the adehabitatLT vignette but continue to get the following error: 

Error in as.ltraj(xy = data[, c("X", "Y")], date = das, id = data$NewID2,  : 
  non unique dates for a given burst

My data is structured as follows: 

*NewID2	       NewDate	 Time	                     X	              Y*
1401FR141732	140403	6:57:00 PM	111111	2222222
1401FR141732	140403	7:37:00 PM	111123	2222243
1401FR141732	140403	7:57:00 PM	111135	2222264
1401FR141732	140403	8:17:00 PM	111147	2222285
1401FR141732	140403	8:37:00 PM	111159	2222306
1401FR141732	140403	8:57:00 PM	111171	2222327
1401FR141732	140403	9:17:00 PM	111183	2222348
1401FR141732	140403	9:37:00 PM	111195	2222369
1401FR141732	140403	9:57:00 PM	111207	2222390
1401FR141732	140403	10:17:00 PM	111219	2222411
1401FR141732	140403	10:37:00 PM	111231	2222432
1401FR141732	140403	11:17:00 PM	111243	2222453

*R-code: *

data<-read.csv("FPT_Ready_for_R_282015.csv")
head(data)

das <- as.character(data$NewDate)
head(das)  
das <- as.POSIXct(strptime(as.character(data$NewDate)

newcoon <- as.ltraj(xy = data[,c("X","Y")], date = das, id=data$NewID2,
burst=data$NewID2,typeII = TRUE)


The NewID2 was designed to be a unique ID for a unique first-passage time
run and date. However, I continue to receive the same error about non unique
dates for a given burst. This doesn't make sense given that I have a
specific run for one animal on a specific date with individual times for
each location. This coding doesn't seem to take into account the time
between successive locations. Maybe I'm missing something.  

Additionally, the data is based on VHF locations; therefore, the time lag
between successive locations is irregular. I eventually need to interpolate
locations every 1-m along the path for the first-passage time analysis and
I'm unclear on the exact process of how to do this using adehabitatLT. 

I appreciate any help on my issues. Thank you! 



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