On May 23, 2011, at 10:52 AM, CAR wrote:

Hi everybody!!

I'm trying to assign boolean values to a column in a matrix depending on the number of times present in another column. I have no clue, I have been 2 days looking for a way, if somebody knows what kind of functions I need to
use I will really apreciate it.

example:

Color Type  Mark1 Mark2 Mark3
Red   high    139    P       alpha
blue   low    140    P        alpha
Green high   141    S       alpha
Yellow low    142   S        beta
Red    high   143    P       gamma

If we only take into account columns Mark1, Mark2 and Mark3. I would like to
ask R to write another column with 0=one; 1=more than one.
If alpha is present for more than one Mark 2, so P and S, then I will like
to assign value 1 if only for one then assign the value 0.

It sounds on a third reading of what not only I seem to be find to be a confusing problem statement that you want both Mark2 and Mark3 to define a basis for counting the number of Mark1 entries and placing the result (possibly duplicated) in another parallel column. If this is so, and the dataframe has a name which we will assume to be `tst` then try:

> tst$count <- with( tst, ave(Mark1, interaction(Mark2, Mark3), FUN=length) )
> tst
   Color Type Mark1 Mark2 Mark3 count
1    Red high   139     P alpha     2
2   blue  low   140     P alpha     2
3  Green high   141     S alpha     1
4 Yellow  low   142     S  beta     1
5    Red high   143     P gamma     1


Thanks for your help


--
View this message in context: 
http://r.789695.n4.nabble.com/How-do-I-assign-boolean-o-1-values-to-a-column-tp3544304p3544304.html
Sent from the R help mailing list archive at Nabble.com.

______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

David Winsemius, MD
West Hartford, CT

______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

Reply via email to