R help - Sep 2005 - Newbie help on dim

Hi, if I do

Z<-rnorm(50)
Followed by
Dim(Z)
I get NULL. Is this correct? Shouldn't I get 50 instead?

TIA
Chris

DISCLAIMER:\ L'utilizzo non autorizzato del presente messagg...{{dropped}}

yes it is correct! look at ?dim() for more info. In this case you need 
length(), i.e.,

Z <- rnorm(50)
length(Z)


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: +32/16/336899
Fax: +32/16/337015
Web: http://www.med.kuleuven.be/biostat/
     http://www.student.kuleuven.be/~m0390867/dimitris.htm



----- Original Message ----- 
From: "Christian Prinoth" <Christian.Prinoth at epsilonsgr.it>
To: <r-help at stat.math.ethz.ch>
Sent: Thursday, September 01, 2005 2:00 PM
Subject: [R] Newbie help on dim

> Hi, if I do
>
> Z<-rnorm(50)
> Followed by
> Dim(Z)
> I get NULL. Is this correct? Shouldn't I get 50 instead?
>
> TIA
> Chris
>
> DISCLAIMER:\ L'utilizzo non autorizzato del presente 
> messagg...{{dropped}}
>
> ______________________________________________
> 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
>

Check out the "dim vs length for vectors" thread:

http://finzi.psych.upenn.edu/R/Rhelp02a/archive/50720.html

This thread goes through the bug-or-feature discussion which is always
entertaining from a socio-R perspective.

Also, note "Dim" with a capital D doesn't exist.

HTH, Andy

> -----Original Message-----
> From: r-help-bounces at stat.math.ethz.ch
> [mailto:r-help-bounces at stat.math.ethz.ch]On Behalf Of Christian Prinoth
> Sent: Thursday, September 01, 2005 8:01 AM
> To: r-help at stat.math.ethz.ch
> Subject: [R] Newbie help on dim
>
>
> Hi, if I do
>
> Z<-rnorm(50)
> Followed by
> Dim(Z)
> I get NULL. Is this correct? Shouldn't I get 50 instead?
>
> TIA
> Chris
>
> DISCLAIMER:\ L'utilizzo non autorizzato del presente
messagg...{{dropped}}
>
> ______________________________________________
> 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
>

Christian Prinoth wrote:
> Hi, if I do
> 
> Z<-rnorm(50)
> Followed by
> Dim(Z)
> I get NULL. Is this correct? Shouldn't I get 50 instead?

No, because Z has no dim attribute. ?dim tells you:

"For an array (and hence in particular, for a matrix) dim retrieves the 
dim attribute of the object. It is NULL or a vector of mode integer."
> TIA
> Chris
> 
> DISCLAIMER:\ L'utilizzo non autorizzato del presente
messagg...{{dropped}}
> 
> ______________________________________________
> 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
Yes, PLEASE do read the posting guide! 
http://www.R-project.org/posting-guide.html


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