R Under development (unstable) (2023-12-09 r85665 ucrt) -- "Unsuffered Consequences"
Copyright (C) 2023 The R Foundation for Statistical Computing
Platform: x86_64-w64-mingw32/x64

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

> library("matrixStats")
> 
> for (mode in c("integer", "double")) {
+   cat("mode: ", mode, "\n", sep = "")
+ 
+   # Empty vector
+   x <- 0
+   storage.mode(x) <- mode
+   y <- prod(x, na.rm = TRUE)
+   print(y)
+   z <- product(x, na.rm = TRUE)
+   print(z)
+   stopifnot(all.equal(z, y))
+ 
+   # Test negative values
+   x <- c(1, -4, 2)
+   storage.mode(x) <- mode
+   y <- prod(x, na.rm = TRUE)
+   print(y)
+   z <- product(x, na.rm = TRUE)
+   print(z)
+   stopifnot(all.equal(z, y))
+ 
+   # Test missing values
+   x <- c(1, NA, NaN, 2)
+   storage.mode(x) <- mode
+   y <- prod(x, na.rm = TRUE)
+   print(y)
+   z <- product(x, na.rm = TRUE)
+   print(z)
+   stopifnot(all.equal(z, y))
+ 
+   x <- c(1, NA, NaN, 2)
+   storage.mode(x) <- mode
+   y <- prod(x, na.rm = FALSE)
+   print(y)
+   z <- product(x, na.rm = FALSE)
+   print(z)
+   stopifnot(all(is.na(z), is.na(y)))
+ 
+   x <- c(1, NaN, 2)
+   storage.mode(x) <- mode
+   y <- prod(x, na.rm = FALSE)
+   print(y)
+   stopifnot(is.na(y))
+   z <- product(x, na.rm = FALSE)
+   print(z)
+   stopifnot(is.na(z))
+ 
+ } # for (mode ...)
mode: integer
[1] 0
[1] 0
[1] -8
[1] -8
[1] 2
[1] 2
[1] NA
[1] NA
[1] NA
[1] NA
mode: double
[1] 0
[1] 0
[1] -8
[1] -8
[1] 2
[1] 2
[1] NA
[1] NA
[1] NaN
[1] NA
> 
> 
> # NAs following 0s
> x <- c(0L, NA_integer_)
> y <- prod(x, na.rm = FALSE)
> print(y)
[1] NA
> z <- product(x, na.rm = FALSE)
> print(z)
[1] NA
> stopifnot(identical(z, y))
> 
> proc.time()
   user  system elapsed 
   0.18    0.01    0.20