Dear Hollie,
ifelse() is one alternative in this particular case:
# Some data
age<- c(46,47,43,46,47,59,50,54,59,60)
ifelse(age<=46, 1,
? ? ? ? ifelse( age>46 & age<=58 , 2, 3) )
[1] 1 2 1 1 2 3 2 2 3 3
See ?ifelse for more details.
HTH,
Jorge
On Thu, Apr 23, 2009 at 8:07 PM, Giggles_Fairy
<giggles_fair... at hotmail.com>wrote:
I have a set of data that includes various data columns. One if the
survival
time and another if a continuous variable of ages. I want to put the ages
into intervals so that I can then perform the Kalpan Meier test. I am
trying
to use the following code to build a column with the age group numbers in
agecatagory<-c( )
for (i in 1:137)
{
{
if(age[i]<=46) ?{agecat[i]<-1}
if(age[i]>46 & age[i]<= 58) {agecat[i]<-2}
if(age[i]>58) {agecat[i]<-3}
}
agecatagory<-c(agecatagory, agecat[i])
}
I have been getting various errors for various things and have finally got
it so that only one error comes up
Error in if (age[i] <= 46) { : missing value where TRUE/FALSE needed
Could anyone pleaseeeeeee shed some light on this for me and tell em where
I
am going wrong. I am sure it is just a minor thing but I cant for the life
of me figure it out!
Your replies will be very much appreciated!