Hi,
May be this helps:
dat1<- read.table(text="
pbnr??????? dat? dep? dys? sop? ago? mis age female
1 10023 1994-02-21 0.75 1.00 0.50 0.50 0.75? 35????? 1
2 10023 1994-05-25 0.75 1.00 0.50 0.50 0.75? 35????? 1
3 10028 1994-02-01 2.00 1.75 3.00 0.50 1.50? 42????? 1
4 10028 1999-01-15 1.25 0.75 2.25 0.50 0.25? 42????? 1
5 10053 1994-03-16 2.50 0.75 1.25 0.50 1.25? 22????? 1
6 10053 1994-09-23 3.25 1.25 1.25 0.75 2.25? 22????? 1
",sep="",header=TRUE,stringsAsFactors=FALSE)
dat1$dat<- as.Date(dat1$dat)
?with(dat1,tapply(dat,list(pbnr),FUN=diff))
#10023 10028 10053
#?? 93? 1809?? 191
library(plyr)
?ddply(dat1,.(pbnr),mutate,Datediff=diff(dat))
?#? pbnr??????? dat? dep? dys? sop? ago? mis age female Datediff
#1 10023 1994-02-21 0.75 1.00 0.50 0.50 0.75? 35????? 1?????? 93
#2 10023 1994-05-25 0.75 1.00 0.50 0.50 0.75? 35????? 1?????? 93
#3 10028 1994-02-01 2.00 1.75 3.00 0.50 1.50? 42????? 1???? 1809
#4 10028 1999-01-15 1.25 0.75 2.25 0.50 0.25? 42????? 1???? 1809
#5 10053 1994-03-16 2.50 0.75 1.25 0.50 1.25? 22????? 1????? 191
#6 10053 1994-09-23 3.25 1.25 1.25 0.75 2.25? 22????? 1????? 191
#or
?dat2<-aggregate(dat~pbnr,data=dat1,diff)
?colnames(dat2)[2]<- "Datediff"
?join(dat1,dat2,by="pbnr")
#?? pbnr??????? dat? dep? dys? sop? ago? mis age female Datediff
#1 10023 1994-02-21 0.75 1.00 0.50 0.50 0.75? 35????? 1????? 93
#2 10023 1994-05-25 0.75 1.00 0.50 0.50 0.75? 35????? 1????? 93
#3 10028 1994-02-01 2.00 1.75 3.00 0.50 1.50? 42????? 1??? 1809
#4 10028 1999-01-15 1.25 0.75 2.25 0.50 0.25? 42????? 1??? 1809
#5 10053 1994-03-16 2.50 0.75 1.25 0.50 1.25? 22????? 1???? 191
#6 10053 1994-09-23 3.25 1.25 1.25 0.75 2.25? 22????? 1???? 191
A.K.
Hi, I am new to this forum, and have a problem. I have data that looks like
this:
pbnr ? ? ? ?dat ?dep ?dys ?sop ?ago ?mis age female
1 10023 1994-02-21 0.75 1.00 0.50 0.50 0.75 ?35 ? ? ?1
2 10023 1994-05-25 0.75 1.00 0.50 0.50 0.75 ?35 ? ? ?1
3 10028 1994-02-01 2.00 1.75 3.00 0.50 1.50 ?42 ? ? ?1
4 10028 1999-01-15 1.25 0.75 2.25 0.50 0.25 ?42 ? ? ?1
5 10053 1994-03-16 2.50 0.75 1.25 0.50 1.25 ?22 ? ? ?1
6 10053 1994-09-23 3.25 1.25 1.25 0.75 2.25 ?22 ? ? ?1
.....
And I want to know how many days each person (pbnr) has been in
therapy. row 1 is first a date for person 10023 and row 2 the second but
what do I do now????
Thanks for you help!!
Sophie
