[R] ask for help

[William Dunlap]

> a<-c(1,1,1,0,0,1,1,1,1,1,1,0,0,0,0,1,1,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1)
> which( a==1 & c(TRUE, a[-length(a)]!=1) )
[1]  1  6 16 23
> which( a==0 & c(TRUE, a[-length(a)]!=0) )
[1]  4 12 18

Bill Dunlap
TIBCO Software
wdunlap tibco.com


On Wed, Aug 6, 2014 at 7:12 PM, Johnnycz <johnnycz at yeah.net> wrote:
> Hello,everybody,
>          I have a sequence,like a<-c(1,1,1,0,0,1,1,1,1,1,1,0,0,0,0,1,1,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1),how to get the position of each first 1 and 0, that's to say, how to get b<-c(1,6,16,23) for first 1 and d<-c(4,12,18) for first 0.
>         Many thanks!
> Johnny
>         [[alternative HTML version deleted]]
>
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