R help - Jul 2011 - transforming a matrix of logical to 0 and 1 while keeping the dim of matrix

Hi all,

Suppose I have a matrix of logical value:

x<-matrix(c(TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE),nrow=3)

I would like to change the value of FALSE to 0 and TRUE to 1. An
obvious way to do it is :
y<-as.numeric(x)

However this method doesn't keep the dim of x. I also need to copy the
dim information to y too.
attributes(y)<-attributes(x)

Is this a correct way to do it in R? Is there any single step function
which can do the something? Thanks


Regards,
TszKin Julian

How about this:
> x<-matrix(c(TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE),nrow=3)
> x
      [,1]  [,2]  [,3]
[1,]  TRUE FALSE  TRUE
[2,] FALSE  TRUE FALSE
[3,]  TRUE FALSE  TRUE
> ifelse(x, 1, 0)
     [,1] [,2] [,3]
[1,]    1    0    1
[2,]    0    1    0
[3,]    1    0    1

Sarah

On Wed, Jul 20, 2011 at 11:16 AM, Julian TszKin Chan <cjulian at bu.edu>
wrote:
> Hi all,
>
> Suppose I have a matrix of logical value:
>
> x<-matrix(c(TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE),nrow=3)
>
> I would like to change the value of FALSE to 0 and TRUE to 1. An
> obvious way to do it is :
> y<-as.numeric(x)
>
> However this method doesn't keep the dim of x. I also need to copy the
> dim information to y too.
> attributes(y)<-attributes(x)
>
> Is this a correct way to do it in R? Is there any single step function
> which can do the something? Thanks
>
>
> Regards,
> TszKin Julian
>
-- 
Sarah Goslee
http://www.functionaldiversity.org

Hi,

I am not sure about "correct", but R stores logical values TRUE/FALSE
as 1/0 already so simply changing the mode would suffice:

mode(x) <- "numeric"

alternately

x + 0

HTH,

Josh

On Wed, Jul 20, 2011 at 8:16 AM, Julian TszKin Chan <cjulian at bu.edu>
wrote:
> Hi all,
>
> Suppose I have a matrix of logical value:
>
> x<-matrix(c(TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE,FALSE,TRUE),nrow=3)
>
> I would like to change the value of FALSE to 0 and TRUE to 1. An
> obvious way to do it is :
> y<-as.numeric(x)
>
> However this method doesn't keep the dim of x. I also need to copy the
> dim information to y too.
> attributes(y)<-attributes(x)
>
> Is this a correct way to do it in R? Is there any single step function
> which can do the something? Thanks
>
>
> Regards,
> TszKin Julian
>
> ______________________________________________
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> PLEASE do read the posting guide
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> and provide commented, minimal, self-contained, reproducible code.
>


-- 
Joshua Wiley
Ph.D. Student, Health Psychology
University of California, Los Angeles
https://joshuawiley.com/