[R] drop observations

[David Winsemius]

On Dec 30, 2010, at 5:53 PM, David Winsemius wrote:

>
> On Dec 30, 2010, at 4:54 PM, Charlène Cosandier wrote:
>
>> Hi,
>>
>> I want to drop observations with value 0 from my data.frame "dta"  
>> for each
>> of the two variables "c01" and "ctotale". How can I do that?

And on second look I wonder if my translation from English to Boolean  
was correct. If you wanted to excluded any case with c01 == 0 or  
ctotal==0 then the code was correct, but if you wanted to exclude only  
case where both were zero, the code would be incorrect and the logical  
operator should be changed to "&".

>>
>> Thanks
>>
>>
>
> subset(dta, !( c01==0 | ctotale==0) )
>
> ... remembering of course to assign this result to some  
> appropriately named object.
>
>
>> Charlène Lisa Cosandier

David Winsemius, MD
West Hartford, CT