[R] create space for a matrix

[Petr PIKAL]

Hi

r-help-bounces at r-project.org napsal dne 29.03.2010 08:41:15:

> Hi Leo,
> 
> see the matrix function e.g. 
> 
> m <- matrix(0, nrow=1, ncol=3)
> 
> then you can use functions like rbind or cbind to create bigger ones.
> 
> I am a newbie so double check everything :)
> 
> HTH,
> Best regards,
> Giovanni
> 
> On Mar 29, 2010, at 8:37 AM, leobon wrote:
> 
> > 
> > Hello all,
> > I want to creat a space for a matrix. 

There is no such "space" for an object. Advisable is to create an object 
with desired final dimensions when using for cycle. However there is not 
many reasons for using cycles, much can be done with vectorised code 
instead.

You can create matrix by 

mat <- matrix(0, nrow, ncol)

or by

mat <- rep(0,nrow*ncol)
dim(mat) <- c(nrow,ncol)

where
nrow is integer number of rows and ncol is integer number of columns

Regards
Petr
 

> > For example, I have a matrix with the dimension of 1(row)*3(col), 
which is
> > (2,3,4). Then I want to put this matrix into a new and larger matrix. 
The
> > dimension of the new matrix is 3*3. So what I want is creating a new 
larger
> > matrix which allows me to put each smaller matrix with the same 
columns into
> > it. 
> > I know 0*(1:3) is the way to creat a space for 3 numbers. Could any 
body
> > tell me how to creat a space for a matrix?
> > Appreciate very much for your help!
> > 
> > Leo
> > -- 
> > View this message in context: http://n4.nabble.com/create-space-for-a-
> matrix-tp1694754p1694754.html
> > Sent from the R help mailing list archive at Nabble.com.
> > 
> > ______________________________________________
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