mnu <- unique(mn[order(mn$m,mn$n),])
mnu$p <- table(paste(mn$m, mn$n))
merge(mnu[sample(1:nrow(mnu), size=3, prob=mnu$p, replace=F), c("m","n")], xy,
by.x=c("m","n"),
by.y=c("x","y"))
---
Jacques VESLOT
CNRS UMR 8090
I.B.L (2ème
merge(mn[sample(1:nrow(mn), 3, rep=F),], xy, by.x=c("m","n"), by.y=c("x","y"))
---
Jacques VESLOT
CNRS UMR 8090
I.B.L (2ème étage)
1 rue du Professeur Calmette
B.P. 245
59019 Lille Cedex
Tel : 33 (0)3.20.87.10.44
Fax : 33 (0)3.20.87.
Dear friends,
suppose i have two datasets: A and B
A:
id<-1:6
x<-c(1,2,3,4,5,6)
y<-c(2,4,6,8,3,2)
xy<-data.frame(id,x,y)
B
m<-c(1,1,3,3,5,5)
n<-c(2,2,6,6,3,3)
mn<-data.frame(m,n)
Now, i want to perfomr two tasks:
1. get a subset of B,no duplicate values,:
C:
m n
1 2
3 6
5 3
2.Extract the values
