[R] way to check if the evaluation of an expression returns an error?

[Andrew Robinson]

?try

Cheers,

Andrew

On Fri, Dec 14, 2007 at 02:10:52PM -0800, Thomas Pujol wrote:
> Is there a recommended or "good" way to check if the evaluation of an expression returns an error?
>    
>   e.g. 
> var(NA)    
>   I wish  var(NA) to return NA or "err", or some other value, even a text-string, but not an error message.
>    
>    
>   I am using a loop to load many samples of data and to perform analysis on each sample.  On occasion, the function I execute returns an error message.  (e.g. when all data is NA, etc).   I wish for the loop to continue to execute, and to have the function return an NA or NULL rather then an error message.
>    
> 
>        
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-- 
Andrew Robinson  
Department of Mathematics and Statistics            Tel: +61-3-8344-9763
University of Melbourne, VIC 3010 Australia         Fax: +61-3-8344-4599
http://www.ms.unimelb.edu.au/~andrewpr
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