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 ??????? Thank you. --------------------------------- [[alternative HTML version deleted]]
See
> help("[")
which informs you about the additional argument "drop":
> ret <-matrix(1,4,4)[i1:i2,j1:j2,drop=FALSE] ;
BTW, you do not need to end lines of code with a ";" ...
Eric
At 12:06 4/11/2004, JC Vaugeois wrote:>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 ???????
>
>Thank you.
>
>
>
>
>
>---------------------------------
>
>
>
>
> [[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
Eric Lecoutre
UCL / Institut de Statistique
Voie du Roman Pays, 20
1348 Louvain-la-Neuve
Belgium
tel: (+32)(0)10473050
lecoutre at stat.ucl.ac.be
http://www.stat.ucl.ac.be/ISpersonnel/lecoutre
If the statistics are boring, then you've got the wrong numbers. -Edward
Tufte
just use
matrix(1,4,4)[i1:i2,j1:j2, drop=FALSE]
Best,
Dimitris
----
Dimitris Rizopoulos
Ph.D. Student
Biostatistical Centre
School of Public Health
Catholic University of Leuven
Address: Kapucijnenvoer 35, Leuven, Belgium
Tel: +32/16/396887
Fax: +32/16/337015
Web: http://www.med.kuleuven.ac.be/biostat/
http://www.student.kuleuven.ac.be/~m0390867/dimitris.htm
----- Original Message -----
From: "JC Vaugeois" <vaugeoisjc at yahoo.fr>
To: <R-help at stat.math.ethz.ch>
Sent: Thursday, November 04, 2004 12:06 PM
Subject: [R] keep dimension of a sub matrix
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 ???????
Thank you.
---------------------------------
[[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
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 (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk) FAX: (+45) 35327907