[R] apply( )

Greg Tarpinian sasprog474 at yahoo.com
Thu May 10 16:39:46 CEST 2007


I have a question that must have a simple answer (but eludes me).
I need a row-by-row logical comparison across three numeric variables
in
a data frame: foo$x, foo$y, foo$z.  The logic is

   if( x < y || x > z ) 1 else 0

for a particular row.

It is simple and very inefficient to use for(i in 1:length(foo$x)){ }
loops.  How can I accomplish this using sappy( ) / lapply( ) / apply( )
or some other more efficient method?

Thank you in advance,

    Greg



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