R help - Oct 2006 - "which" command

I obtained error messages when I run these commands in UNIX, but I 
obtained correct result when I run these command in WINDOWS.  Can 
somebody point out the problem and give the solution. Thanks.

 > dt<-read.table(file="Fall.dat")
 > dim(dt)
[1] 1941    5
 > table(dt$V2)
  0   1   2   3
220 989 639  93
 >
 > Favg<-as.matrix(c(1:max(dt$V2)))
 >
 > for(i in 1:max(dt$V2)){Favg[i]<-mean(dt[which(dt[,2] == i),5])}
 > Favg
     [,1]
[1,]   NA
[2,]   NA
[3,]   NA
Warning messages:
argument is not numeric or logical: returning NA (etc)

I obtained error messages when I run these commands in UNIX, but I 
obtained correct result when I run these command in WINDOWS.  Can 
somebody point out the problem and give the solution. Thanks.

 > dt<-read.table(file="Fall.dat")
 > dim(dt)
[1] 1941    5
 > table(dt$V2)
  0   1   2   3
220 989 639  93
 >
 > Favg<-as.matrix(c(1:max(dt$V2)))
 >
 > for(i in 1:max(dt$V2)){Favg[i]<-mean(dt[which(dt[,2] == i),5])}
 > Favg
     [,1]
[1,]   NA
[2,]   NA
[3,]   NA
Warning messages:
argument is not numeric or logical: returning NA (etc)


Cheers,
@

Are you sure Fall.dat is identical on both platforms, and that dt is also?
Did you intend to ignore the cases where dt$V2 equals zero?

Try, for example,
   table(which(dt[,2] == 0))   ## also ==1, ==2, ==3
   unique(  dt[which(dt[,2] == 0),5]    ## also ==1, ==2, ==3
   unique( dt$V5 )
  adding na.rm=TRUE to mean()


Also, try this:
   tmp <- lapply( split( dt$V5, dt$V2) , mean )
   Favg <- unlist(tmp)

-Don

At 4:57 PM -0400 10/5/06, AgusSusanto wrote:
>I obtained error messages when I run these commands in UNIX, but I
>obtained correct result when I run these command in WINDOWS.  Can
>somebody point out the problem and give the solution. Thanks.
>
>  > dt<-read.table(file="Fall.dat")
>  > dim(dt)
>[1] 1941    5
>  > table(dt$V2)
>   0   1   2   3
>220 989 639  93
>  >
>  > Favg<-as.matrix(c(1:max(dt$V2)))
>  >
>  > for(i in 1:max(dt$V2)){Favg[i]<-mean(dt[which(dt[,2] == i),5])}
>  > Favg
>      [,1]
>[1,]   NA
>[2,]   NA
>[3,]   NA
>Warning messages:
>argument is not numeric or logical: returning NA (etc)
>
>______________________________________________
>R-help at stat.math.ethz.ch mailing list
>https://stat.ethz.ch/mailman/listinfo/r-help
>PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
>and provide commented, minimal, self-contained, reproducible code.

-- 
--------------------------------------
Don MacQueen
Environmental Protection Department
Lawrence Livermore National Laboratory
Livermore, CA, USA

AgusSusanto <gusanto <at> gmail.com> writes:
> 
> I obtained error messages when I run these commands in UNIX, but I 
> obtained correct result when I run these command in WINDOWS.  Can 
> somebody point out the problem and give the solution. Thanks.
> 
>  > dt<-read.table(file="Fall.dat")
>  > dim(dt)
> [1] 1941    5
Windows file names are not case sensitive, UNIX is. Check you effective
filename.

Dieter