fwrite ignores options(scipen = 999)

[florianWickler]

Hey,

I use options(scipen = 999) to avoid scientific notation. write.table() uses this option, but not fwrite() (data.table 1.10.0).

Example:

options(scipen = 999)
library(data.table)
dt <- data.table(a = 0.0001, b = 10^6)
write.table(dt, file = "wt.csv", row.names = FALSE)
fwrite(dt, file = "fw.csv")

[apprent]

library(data.table)

aaa <- data.table(c(10, 100, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, 1e10, 
                    1e11, 1e12, 1e13, 1e14, 1e15, 1e16))

options(scipen = 0)
write.csv(aaa, "scipen-0-writecsv.txt")
fwrite(aaa, "scipen-0-fwrite.txt")


options(scipen = 3)
write.csv(aaa, "scipen-3-writecsv.txt")
fwrite(aaa, "scipen-3-fwrite.txt")


options(scipen = 5)
write.csv(aaa, "scipen-5-writecsv.txt")
fwrite(aaa, "scipen-5-fwrite.txt")


options(scipen = 10)
write.csv(aaa, "scipen-10-writecsv.txt")
fwrite(aaa, "scipen-10-fwrite.txt")


options(scipen = 99)
write.csv(aaa, "scipen-99-writecsv.txt")
fwrite(aaa, "scipen-99-fwrite.txt")

[ajnisbet]

Looks like this is hardcoded in fwrite.c?

One workaround is to cast integer columns with bit64::as.integer64.

[mattdowle]

And fwrite() tests in test.data.table() are affected by user setting options(scipen=) reported here with screenshots : https://twitter.com/ilarischeinin/status/1085082345013739520

[sjain777]

Turning off scientific notation in fwrite not working is an issue. Any attempt to reformat the data using standard R functions add slowness to a big-data use-case. Hence, getting this addressed in 1.12.4 as indicated above would be awesome, thanks much!