Zany stuff that happens in R 3.0.2 on OS X: some cool, some absolutely awful

zany.R

M <- matrix(c(1, 0, 0, 1), byrow = 1, nrow = 2)
df <- data.frame(A = 1)
df$B <- list(M)
df
#  A          B
#  1 1, 0, 0, 1

zany2.R

# Only works on some platforms: this was on OS X 10.9 with R version 3.0.1 (2013-05-16) -- "Good Sport"
NaN + NA_real_
# [1] NaN
NA_real_ + NaN
# [1] NA

zany3.R

x <- c(1, 2, 3, 4)
x[NA]
# [1] NA NA NA NA
x[TRUE]
# [1] 1 2 3 4

zany4.R

data <- "MySQLID\n1000\n1001"
 
ids <- read.csv(text = data)
 
ids[1, 1] == ids[2, 1]
# [1] FALSE

data <- "MySQLID\n100000000000000000\n100000000000000001"

ids <- read.csv(text = data)
 
ids[1, 1] == ids[2, 1]
# [1] TRUE

Output is slightly misleading (at least to me) as the first 1 is the row name.

print(df,row.names=FALSE)
#A          B
#1 1, 0, 0, 1

Good point. Changed to remove row name.