[R] keep dimension of a sub matrix

[Peter Dalgaard]

JC Vaugeois <vaugeoisjc at yahoo.fr> writes:

> Hi,
> is there any way to keep a sub matrix dimension?
>  
> exemple :
> i1<-1; i2<-1
> j1<-2; j2<-3;
> ret <-matrix(1,4,4)[i1:i2,j1:j2] ;
>  
> dim(ret) is NULL because the submatrix single col or single row is coerce to a vector automaticaly.
> How can i bypass this cast  : submatrix->vector   ???????

help("[") 

drop=FALSE is what you're looking for

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
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