[R] missing values
uleopold at science.uva.nl
Thu Jun 27 10:40:25 CEST 2002
Renaud Lancelot wrote:
> tapply(lsk0t50$Pox2, lsk0t50$ProfN, function(x) sum(x[!is.na(x)]) )
Also for your suggestion I get the same strange result. It seems that the
following columns interfere with the variable(Pox2) column because the
missing values are omitted, excluded etc.
So maybe I am using the wrong command by using tapply?
I have a data object with several columns and would like to sum one column
by a factor given in antother column but omitting, excluding the NAs.
> Ulrich Leopold wrote:
>>how can I exclude the missing values in the following example:
>>tapply(lsk0t50$Pox2, lsk0t50$ProfN, sum)
>>tapply(lsk0t50$Pox2, lsk0t50$ProfN, sum, Fun=is.na(lsk0t50$Pox2))
>>But it returns a lot of missing values in the result. Instead the missing
>>values in the variable should not be taken into account. So that I get only
>>a NA as result if there are only NAs for the corresponding factor.
>>Any idea how this can be achieved?
>>Ulrich Leopold MSc.
>>Department of Physical Geography
>>Institute for Biodiversity and Ecosystem Dynamics
>>Faculty of Science
>>University of Amsterdam
>>Nieuwe Achtergracht 166
>>Phone: +31-(0)20-525-7456 (7451 Secretary)
>>Email: uleopold at science.uva.nl
>>Check us also out at:
>>Netherlands Centre for Geo-ecological Research
>>r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
>>Send "info", "help", or "[un]subscribe"
>>(in the "body", not the subject !) To: r-help-request at stat.math.ethz.ch
Ulrich Leopold MSc.
Department of Physical Geography
Institute for Biodiversity and Ecosystem Dynamics
Faculty of Science
University of Amsterdam
Nieuwe Achtergracht 166
Phone: +31-(0)20-525-7456 (7451 Secretary)
Email: uleopold at science.uva.nl
Check us also out at:
Netherlands Centre for Geo-ecological Research
r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !) To: r-help-request at stat.math.ethz.ch
More information about the R-help