[R] What does uniroot return when an error occurs

[William Dunlap]

?tryCatch

As in:
> tryCatch(uniroot( function(x) x^2+1, lower=1, upper=2 )$root, error=function(e){warning(conditionMessage(e)); NA})
Warning in value[[3L]](cond) :
  f() values at end points not of opposite sign
[1] NA
> tryCatch(uniroot( function(x) x^2-1.5, lower=1, upper=2 )$root, error=function(e){warning(conditionMessage(e)); NA})
[1] 1.224745

Bill Dunlap
Spotfire, TIBCO Software
wdunlap tibco.com


> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] On Behalf
> Of asafwe
> Sent: Thursday, November 01, 2012 1:00 PM
> To: r-help at r-project.org
> Subject: [R] What does uniroot return when an error occurs
> 
> Hi,
> 
> I'm using the uniroot function, and would like to detect an error which
> occurs, for instance, when the values at endpoints are not of opposite
> signs. For example:
> 
> uniroot( function(x) x^2+1, lower=1, upper=2 ).
> 
> I want to say something like:
> 
> if "error in uniroot(...)" return NA else return uniroot$root
> 
> Thanks a lot!
> 
> Asaf
> 
> 
> 
> --
> View this message in context: http://r.789695.n4.nabble.com/What-does-uniroot-
> return-when-an-error-occurs-tp4648168.html
> Sent from the R help mailing list archive at Nabble.com.
> 
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