[R] Conditionals for Errors or error flags

[Ramon Diaz-Uriarte]

Dear Jon,

You probably want to take a look at "try" and "tryCatch".  Either of
them will let you do what you want.

Best,

R.

On Sat, Mar 15, 2008 at 7:00 PM, Jon Loehrke <jloehrke at umassd.edu> wrote:
> Greetings,
>
>  I have been working on a script that conducts repeated statistics and
>  plots to my data.  In this case it is sub-setting the dataframe by
>  month.
>  The intent is to develop a custom analysis and plotting that I can run
>  on a large number of data sets.
>
>  Unfortunately, a small portion of my subsets (~1%) cause an error with
>  one of the wrapped subroutines that results in the whole routine
>  aborting.  It would be incredibly difficult to find the cause of this
>  error post-run, and the particular routine does not have a way of
>  treating the error (it isn't as simple as NA, etc.)
>
>  What I am wondering is if there is a corollary to the conditional
>  is.na() such as is.error()? Or is there a way to get some other output
>  from an error than an abort?
>
>  That I can use to toggle between a process that causes an error and
>  one that doesn't without aborting the whole shebang.
>
>  Any ideas are appreciated.
>
>
>  I apologize that I could not think up an example so I included a
>  psuedo-code below.
>
>  do.something<-function(x){
>         run other scripts with data, possibly causing an error
>  }
>
>  do.something.else<-function(x){
>         Something that doesn't cause an error
>  }
>
>  run.prog<-function(x){
>
>         if(IS.ERROR(do.something)){do.something.else}else{do.something}  #or
>  flag error
>  }
>
>  run.prog(data)
>  #runs everything if there is an error it does not abort with error but
>  rather does something else that doesn't error and continues.
>
>  Thank you very much,
>
>  Jon
>  R 2.6.2
>  MAC OS 10.5
>
>  Jon Loehrke
>  Graduate Research Assistant
>  Department of Fisheries Oceanography
>  School for Marine Science and Technology
>  University of Massachusetts
>  200 Mill Road, Suite 325
>  Fairhaven, MA 02719
>  jloehrke at umassd.edu
>  508-758-6393
>
>  ______________________________________________
>  R-help at 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.
>



-- 
Ramon Diaz-Uriarte
Statistical Computing Team
Structural Biology and Biocomputing Programme
Spanish National Cancer Centre (CNIO)
http://ligarto.org/rdiaz