[R] NULL

[Peter Alspach]

Tena koe Yu

?is.null

HTH ...


Peter Alspach

> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of Yuan Jian
> Sent: Monday, 26 July 2010 5:05 p.m.
> To: r-help at r-project.org
> Subject: [R] NULL
> 
> hi,
> I have a simple problem.
> 
> how can I test whether a variable is NULL?
> 
> a = NULL
> if (a == NULL){
> ...
> }
> it seems not work
> 
> thanks
> 
> YU
> 
> 
> 
> 
> 
> 
> 	[[alternative HTML version deleted]]
> 
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