There is pmin and pmax each taking na.rm, why no psum?
r
Solution
Following @JoshUlrich's comment on the previous question,
psum <- function(...,na.rm=FALSE) {
rowSums(do.call(cbind,list(...)),na.rm=na.rm) }
edit: from Sven Hohenstein:
psum2 <- function(...,na.rm=FALSE) {
dat <- do.call(cbind,list(...))
res <- rowSums(dat, na.rm=na.rm)
idx_na <- !rowSums(!is.na(dat))
res[idx_na] <- NA
res
}
x = c(1,3,NA,5,NA)
y = c(2,NA,4,1,NA)
z = c(1,2,3,4,NA)
psum(x,y,na.rm=TRUE)
## [1] 3 3 4 6 0
psum2(x,y,na.rm=TRUE)
## [1] 3 3 4 6 NA
n = 1e7
x = sample(c(1:10,NA),n,replace=TRUE)
y = sample(c(1:10,NA),n,replace=TRUE)
z = sample(c(1:10,NA),n,replace=TRUE)
library(rbenchmark)
benchmark(psum(x,y,z,na.rm=TRUE),
psum2(x,y,z,na.rm=TRUE),
pmin(x,y,z,na.rm=TRUE),
pmax(x,y,z,na.rm=TRUE), replications=20)
## test replications elapsed relative
## 4 pmax(x, y, z, na.rm = TRUE) 20 26.114 1.019
## 3 pmin(x, y, z, na.rm = TRUE) 20 25.632 1.000
## 2 psum2(x, y, z, na.rm = TRUE) 20 164.476 6.417
## 1 psum(x, y, z, na.rm = TRUE) 20 63.719 2.486
Sven's version (which arguably is the correct one) is quite a bit slower, although whether it matters obviously depends on the application. Anyone want to hack up an inline/Rcpp version?
As for why this doesn't exist: don't know, but good luck getting R-core to make additions like this ... I can't offhand think of a sufficiently widespread `*misc` package into which this could go ...
Follow up thread by Matthew on r-devel is here (which seems to confirm) : r-devel: There is pmin and pmax each taking na.rm, how about psum?
Problem
It seems that R might be missing an obvious simple function: `psum`. Does it exist as a different name, or is it in a package somewhere? ``` x = c(1,3,NA,5) y = c(2,NA,4,1) min(x,y,na.rm=TRUE) # ok [1] 1 max(x,y,na.rm=TRUE) # ok [1] 5 sum(x,y,na.rm=TRUE) # ok [1] 16 pmin(x,y,na.rm=TRUE) # ok [1] 1 3 4 1 pmax(x,y,na.rm=TRUE) # ok [1] 2 3 4 5 psum(x,y,na.rm=TRUE) [1] 3 3 4 6 # expected result Error: could not find function "psum" # actual result ``` I realise that `+` is already like `psum`, but what about `NA`? ``` x+y [1] 3 NA NA 6 # can't supply `na.rm=TRUE` to `+` ``` Is there a case to add `psum`? Or have I missed something. This question is a follow up from this question : Using `:=` in data.table to sum the values of two columns in R, ignoring NAs