[R] Changing zeros to NAs in a data frame

[Laura Holt]

Dear R People:

I have a data frame with some columns that are numeric and some which are 
factors.

There are zeros in the numeric columns and I would like to change them to 
NAs.  However, there are zeros in some of the factor columns, and I would 
like them to be left alone.

Is there a "global" way to do this, please?  I was thinking about use the 
results from "str" but am not sure.

R Version 2.0.0 Windows.

Thanks in advance.
Sincerely,
Laura Holt
mailto: lauraholt_983 at hotmail.com


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