[R] merge question

[Dr Eberhard W Lisse]

Thank you very much.

el

On 2014-06-30, 00:48 , Rolf Turner wrote:
> 
> On 30/06/14 10:32, Dr Eberhard W Lisse wrote:
> 
>> Thanks,
>>
>> I then set NA to 0, and can do the sutraction,
>>
>> great.
> 
> Not so great.  I haven't gone through the issues underlying this post,
> but replacing NA by 0 will almost surely yield nonsense.  "Missing" is
> ***not*** the same thing as "zero".  Pretending that it is will have
> disastrous consequences.  Think through what you are trying to do more
> clearly.
> 
> cheers,
> 
> Rolf Turner