setting a number of values to NA over a data.frame.

Jim Lemon <jim <at> bitwrit.com.au> writes:

Hi John,
You might have a look at "toNA" in the prettyR

package. Wait for version 

1.0-4, just uploaded, as I have fixed a bug in

that function.

There is also a set of generic functions exactly for
such cases: unknownToNA(),
NAToUnknown() and isUnknown() in gdata package.

Gregor