R help - Apr 2012 - binned tabulation

Hi,

I am attempting to tabulate binned data. The '1' represents the
appearance of the focal mouse pup, and '2' represents the disappearance
of the focal mouse pup. The code written below is intended to calculate the
total time spent appeared out of 3600s. For Sample 1, both the hand calculation
and R code yield the same result, 50. A problem seems to occur when '1'
is the last entry. For Sample 2, the total time appeared is 53  (hand
calculation), however, using the R code below yields 55. If you have any
suggestions for solving the problem, please let me know. 

Thank you in advance for any assistance you may provide.

Delia


Sample 1

0.0 1
40 2
45 1
55 2


Sample 2

0.0 1
40 2
45 1
55 2
57 1



name = read.table(file.choose(),header=F) # opening a data file
colnames(name)<-c("Time", "Behavior")
name = data.frame(name$Behavior, name$Time)
colnames(name)<-c("Behavior", "Time")    
name<-name[name$Time < 3600, ];

## run file 

x<-seq(0,3600, by = 60) # total time partition by time which is 60

if (tail(name$Behavior, 1) == 1) {name<-rbind(name, c(4, 3600))} else
{name<-rbind(name, c(1, 3600))} 

if (nrow(name) %% 2 != 0)
 {name <-name[-c(nrow(name)), -c(nrow(name))]}

q<-NULL
for (y in (1: nrow(name)))
{
    if (y %% 2 != 0)
    q<-c(q, (c(name$Time[y]:name$Time[y +1])))
}

b<-table(cut(q,x))

sum(b)

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Delia,

name <- data.frame(Behavior=c(1, 2, 1, 2, 1), Time=c(0, 40, 45, 55, 57))

appear <- name$Time[name$Behavior==1]
disappear <- name$Time[name$Behavior==2]
if(length(appear) > length(disappear)) disappear <- c(disappear, 60)
sum(disappear - appear)

Delia Shelton wrote on 04/09/2012 12:30:23 PM:
> Hi,
> 
> I am attempting to tabulate binned data. The '1' represents the 
> appearance of the focal mouse pup, and '2' represents the 
> disappearance of the focal mouse pup. The code written below is 
> intended to calculate the total time spent appeared out of 3600s. 
> For Sample 1, both the hand calculation and R code yield the same 
> result, 50. A problem seems to occur when '1' is the last entry.
For
> Sample 2, the total time appeared is 53  (hand calculation), 
> however, using the R code below yields 55. If you have any 
> suggestions for solving the problem, please let me know. 
> 
> Thank you in advance for any assistance you may provide.
> 
> Delia
> 
> 
> Sample 1
> 
> 0.0 1
> 40 2
> 45 1
> 55 2
> 
> 
> Sample 2
> 
> 0.0 1
> 40 2
> 45 1
> 55 2
> 57 1
> 
> 
> 
> name = read.table(file.choose(),header=F) # opening a data file
> colnames(name)<-c("Time", "Behavior")
> name = data.frame(name$Behavior, name$Time)
> colnames(name)<-c("Behavior", "Time")    
> name<-name[name$Time < 3600, ];
> 
> ## run file 
> 
> x<-seq(0,3600, by = 60) # total time partition by time which is 60
> 
> if (tail(name$Behavior, 1) == 1) {name<-rbind(name, c(4, 3600))} else
> {name<-rbind(name, c(1, 3600))} 
> 
> if (nrow(name) %% 2 != 0)
>  {name <-name[-c(nrow(name)), -c(nrow(name))]}
> 
> q<-NULL
> for (y in (1: nrow(name)))
> {
>     if (y %% 2 != 0)
>     q<-c(q, (c(name$Time[y]:name$Time[y +1])))
> }
> 
> b<-table(cut(q,x))
> 
> sum(b)
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