R help - Jun 2007 - create matrix from comparing two vectors

hi all, sorry for this basic question, I think I know I should use ?apply, but
it is really confusing me...

I want to create a matrix by comparing two vectors.  Eg:

test<-seq(1:10)
fac<-c(3,6,9)

and i want to end up with a 10*3 matrix with a boolean that tests if
test<fac, so something like:

1 1 1
1 1 1
0 1 1
0 1 1
0 1 1
0 0 1
0 0 1
0 0 1
0 0 0
0 0 0

I can't find the solution without using a loop...

B

	[[alternative HTML version deleted]]

outer(test, fac, "<")

-b

On Jun 26, 2007, at 2:13 PM, Van Campenhout Bjorn wrote:
> hi all, sorry for this basic question, I think I know I should use ? 
> apply, but it is really confusing me...
>
> I want to create a matrix by comparing two vectors.  Eg:
>
> test<-seq(1:10)
> fac<-c(3,6,9)
>
> and i want to end up with a 10*3 matrix with a boolean that tests  
> if test<fac, so something like:
>
> 1 1 1
> 1 1 1
> 0 1 1
> 0 1 1
> 0 1 1
> 0 0 1
> 0 0 1
> 0 0 1
> 0 0 0
> 0 0 0
>
> I can't find the solution without using a loop...
>
> B
>
> 	[[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at stat.math.ethz.ch 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.

try this:

test <- 1:10
fac <- c(3, 6, 9)

outer(test, fac, "<") * 1


I hope it helps.

Best,
Dimitris

----
Dimitris Rizopoulos
Ph.D. Student
Biostatistical Centre
School of Public Health
Catholic University of Leuven

Address: Kapucijnenvoer 35, Leuven, Belgium
Tel: +32/(0)16/336899
Fax: +32/(0)16/337015
Web: http://med.kuleuven.be/biostat/
      http://www.student.kuleuven.be/~m0390867/dimitris.htm


Quoting Van Campenhout Bjorn <bjorn.vancampenhout at ua.ac.be>:
> hi all, sorry for this basic question, I think I know I should use   
> ?apply, but it is really confusing me...
>
> I want to create a matrix by comparing two vectors.  Eg:
>
> test<-seq(1:10)
> fac<-c(3,6,9)
>
> and i want to end up with a 10*3 matrix with a boolean that tests if  
>  test<fac, so something like:
>
> 1 1 1
> 1 1 1
> 0 1 1
> 0 1 1
> 0 1 1
> 0 0 1
> 0 0 1
> 0 0 1
> 0 0 0
> 0 0 0
>
> I can't find the solution without using a loop...
>
> B
>
> 	[[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at stat.math.ethz.ch 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.
>
>


Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm

In case you really want to use the apply variety, here is another one,

 sapply(fac,function(x)ifelse(test/x<1, 1, 0))

H.
>>> "Van Campenhout Bjorn" <bjorn.vancampenhout at
ua.ac.be> 6/26/2007 11:13:14 AM >>>
hi all, sorry for this basic question, I think I know I should use ?apply, but
it is really confusing me...

I want to create a matrix by comparing two vectors.  Eg:

test<-seq(1:10)
fac<-c(3,6,9)

and i want to end up with a 10*3 matrix with a boolean that tests if
test<fac, so something like:

1 1 1
1 1 1
0 1 1
0 1 1
0 1 1
0 0 1
0 0 1
0 0 1
0 0 0
0 0 0

I can't find the solution without using a loop...

B

	[[alternative HTML version deleted]]

______________________________________________
R-help at stat.math.ethz.ch 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.