On Tue, Sep 18, 2012 at 5:35 PM, David Winsemius <dwinsem...@comcast.net> wrote: > > On Sep 18, 2012, at 5:10 PM, John Sorkin wrote: > >> Window 7 >> R 2.15 >> >> I am writing a simulation which generates sample sized estimates from >> simulated data. When I run the function shown below, >> power.t.test(delta=14.02528,sd=1.945226,power=0.8,sig.level=0.05) >> >> I get an error message: >> >>> power.t.test(delta=14.02528,sd=1.945226,power=0.8,sig.level=0.05) >> Error in uniroot(function(n) eval(p.body) - power, c(2, 1e+07)) : >> f() values at end points not of opposite sign >> >> The fact that the function can not return a sample size is OK, however I >> need to trap the error and set the sample size equal to NA. How do I trap >> the error so that when the error occurs I can set sample size equal to NA? > > ?conditions #### has lots of fancy stuff > # But I use just plain old `try` > > test=-10:10 > sapply(test, function(x) if( "try-error" %in% > class( try( test[test[x:1]] ) ) ){ > 2}else{0} ) > Error in test[x:1] : only 0's may be mixed with negative subscripts > Error in test[x:1] : only 0's may be mixed with negative subscripts > Error in test[x:1] : only 0's may be mixed with negative subscripts > Error in test[x:1] : only 0's may be mixed with negative subscripts > Error in test[x:1] : only 0's may be mixed with negative subscripts > Error in test[x:1] : only 0's may be mixed with negative subscripts > Error in test[x:1] : only 0's may be mixed with negative subscripts > Error in test[x:1] : only 0's may be mixed with negative subscripts > Error in test[x:1] : only 0's may be mixed with negative subscripts > Error in test[x:1] : only 0's may be mixed with negative subscripts > [1] 2 2 2 2 2 2 2 2 2 2 0 0 0 0 0 0 0 0 0 0 0 > > You still get the messages but the code runs.
Just to add - if the messages bother you (they would bother me since normally an error message indicates the function aborted), you can add argument silent = TRUE to the try() call. Peter ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.