The following function expects a logical input and maps NA entries to FALSE: is.true <- function(x) !is.na(x) & x E.g., > z <- c(1,2,3,NA,5,6) > is.true(z>2.5 & z<5.5) [1] FALSE FALSE TRUE FALSE TRUE FALSE
Bill Dunlap Spotfire, TIBCO Software wdunlap tibco.com > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On > Behalf > Of Anthony Damico > Sent: Wednesday, June 20, 2012 2:19 PM > To: R. Michael Weylandt > Cc: r-help@r-project.org > Subject: Re: [R] binary operators that never return missing values > > Thanks Michael, > > I was hoping to complete this in one step (since I use these a lot). > Setting the class of the vectors seems like more typing than just > doing %>F% ... > > Unfortunately, my knowledge of classes, methods, and the like is > pretty shaky. Is it possible to *create* another set of operators > that just changes NAs to falses or trues?-- > > >F <F >=F <=F >T <T >=T <=T > > I definitely don't want to change the base functionality of the > operators, so infix notation seems like the strategy that will require > the least typing in the long run.. but my mind is still open. :) > > > > On Wed, Jun 20, 2012 at 4:54 PM, R. Michael Weylandt > <michael.weyla...@gmail.com> wrote: > > Hi Anthony, > > > > No, I don't believe this exists on CRAN already (happy to be proven > > wrong though) but I might suggest you approach things a different way: > > instead of defining this operator by operator with infix notation, why > > not go after `+`, `>` directly? If you put a class on your vectors, > > you can define Ops.class which will change the behavior of all those > > sorts of things. > > > > Simple example (probably not complete nor necessarily advisable) > > > > a <- c( 1 , NA , 7 , 2 , NA ) > > b <- c( NA , NA , 9 , 1 , 6 ) > > > > class(a) <- class(b) <- "damico" > > > > Ops.damico <- function(e1, e2 = NULL){ > > e1[is.na(e1)] <- 0 > > e2[is.na(e2)] <- 0 > > NextMethod() > > } > > > > a < b > > > > More nuance is available, but this hopefully gives you a start. You > > might, e.g., think about setting this as something more like: > > > > Ops.damico <- function(e1, e2 = NULL){ > > if(.Generic %in% c("==","!=","<","<=",">=",">")){ > > e1[is.na(e1)] <- 0 > > e2[is.na(e2)] <- 0 > > } > > NextMethod() > > } > > > > so you don't mess up arithmetic but only the boolean comparisons. > > > > Best, > > Michael > > > > On Wed, Jun 20, 2012 at 3:44 PM, Anthony Damico <ajdam...@gmail.com> wrote: > >> Hi, I work with data sets with lots of missing values. We often need > >> to conduct logical tests on numeric vectors containing missing values. > >> I've searched around for material and conversations on this topic, > >> but I'm having a hard time finding anything. Has anyone written a > >> package that deals with this sort of thing? All I want are a group of > >> functions like the ones I've posted below, but I'm worried I'm > >> re-inventing the wheel.. If they're not already on CRAN, I feel like > >> I should add them. Any pointers to work already completed on this > >> subject would be appreciated. Thanks! > >> > >> Anthony Damico > >> Kaiser Family Foundation > >> > >> > >> > >> Here's a simple example of what I need done on a regular basis: > >> > >> #two numeric vectors > >> a <- c( 1 , NA , 7 , 2 , NA ) > >> > >> b <- c( NA , NA , 9 , 1 , 6 ) > >> > >> #this has lots of NAs > >> a > b > >> > >> #save this result in x > >> x <- (a > b) > >> > >> #overwrite NAs in x with falses (which we do a lot) > >> x <- ifelse( is.na( x ) , F , x ) > >> > >> #now x has only trues and falses > >> x > >> > >> > >> > >> ################ > >> Here's an example function that solves the problem for "greater than" > >> ################ > >> > >> > >> #construct a function that performs the same steps: > >> "%>F%" <- > >> function( a , b ){ > >> > >> x <- (a > b) > >> > >> x.false <- ifelse( is.na( x ) , F , x ) > >> > >> x.false > >> > >> } > >> > >> #run the function > >> > >> a %>F% b > >> > >> ______________________________________________ > >> R-help@r-project.org mailing list > >> https://stat.ethz.ch/mailman/listinfo/r-help > >> PLEASE do read the posting guide > >> http://www.R-project.org/posting-guide.html > >> and provide commented, minimal, self-contained, reproducible code. > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
