R devel - Jun 2017 - spurious warning in ave()

Consider the following simple data set and a call to ave:

 > tdata <- data.frame(f1=c(1,1,1,1,2,2,2,2), f2=c(1,2,1,2,1,1,1,1),
y=1:8)
 > with(tdata, table(f1, f2))
    f2
f1  1 2
   1 2 2
   2 4 0

 > with(tdata, ave(y, f1, f2, FUN=max))

[1] 3 4 3 4 8 8 8 8
Warning message:
In FUN(X[[i]], ...) : no non-missing arguments to max; returning -Inf

There are no missing values in the result.  The fact that ave() apparently tried
to find
the max for a combination it did not need is irrelvant to the user, and the
warning is
counterproductive.

Terry T.

You can avoid the warnings and the unneeded calls to FUN by adding
drop=TRUE to the call to ave(), since all of its ... arguments are passed
to interaction (I think).

In TERR we dealt with this problem by adding drop=TRUE to ave's
argument list and we pass ... and drop=drop to interaction.  I'm not sure
drop=FALSE is ever desirable.


Bill Dunlap
TIBCO Software
wdunlap tibco.com

On Wed, Jun 14, 2017 at 6:02 AM, Therneau, Terry M., Ph.D. <
therneau at mayo.edu> wrote:
> Consider the following simple data set and a call to ave:
>
> > tdata <- data.frame(f1=c(1,1,1,1,2,2,2,2), f2=c(1,2,1,2,1,1,1,1),
y=1:8)
> > with(tdata, table(f1, f2))
>    f2
> f1  1 2
>   1 2 2
>   2 4 0
>
> > with(tdata, ave(y, f1, f2, FUN=max))
>
> [1] 3 4 3 4 8 8 8 8
> Warning message:
> In FUN(X[[i]], ...) : no non-missing arguments to max; returning -Inf
>
> There are no missing values in the result.  The fact that ave() apparently
> tried to find the max for a combination it did not need is irrelvant to the
> user, and the warning is counterproductive.
>
> Terry T.
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
>
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