Hi r-help-bounces at r-project.org napsal dne 24.02.2009 06:23:23:
Hi R users, I have a question. How can I use for loop to do pair comparisons. For example,
x<-c(1,2,3)
result<-matrix(data=NA, nrow=choose(3,2), ncol=1)
for(i in 1: length(x))
+ { result[i,]<-ifelse(x[i] > x[i+1], yes="Big", no="Small")
+ result}
result
[,1]
[1,] "Small"
[2,] "Small"
[3,] NA
Well. It is a little cryptic what you want. Suppose you have 100 x values. What is x value number 101? If you want to check if subsequent value is bigger or smaller then previous one use diff(x) and test diff(x)>0. Regards Petr
I want to compare (1 vs. 2), (1 vs. 3), (2 vs.3) I know I miss something but I just can not get it work. Could anyone
give me
a hint? Appreciate, Chunhao [[alternative HTML version deleted]]
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