[Rd] bug in sum() on integer vector

Hervé Pagès
Fri, 09 Dec 2011 18:40:55 -0000

Hi,

   x <- c(rep(1800000003L, 10000000), -rep(1200000002L, 15000000))

This is correct:

   > sum(as.double(x))
   [1] 0

This is not:

   > sum(x)
   [1] 4996000

Returning NA (with a warning) would also be acceptable for the latter.
That would make it consistent with cumsum(x):

   > cumsum(x)[length(x)]
   [1] NA
   Warning message:
   Integer overflow in 'cumsum'; use 'cumsum(as.numeric(.))'

Thanks!
H.

 > sessionInfo()
R version 2.14.0 (2011-10-31)
Platform: x86_64-unknown-linux-gnu (64-bit)

locale:
  [1] LC_CTYPE=en_CA.UTF-8       LC_NUMERIC=C
  [3] LC_TIME=en_CA.UTF-8        LC_COLLATE=en_CA.UTF-8
  [5] LC_MONETARY=en_CA.UTF-8    LC_MESSAGES=en_CA.UTF-8
  [7] LC_PAPER=C                 LC_NAME=C
  [9] LC_ADDRESS=C               LC_TELEPHONE=C
[11] LC_MEASUREMENT=en_CA.UTF-8 LC_IDENTIFICATION=C

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base

--
Herv? Pag?s

Program in Computational Biology
Division of Public Health Sciences
Fred Hutchinson Cancer Research Center
1100 Fairview Ave. N, M1-B514
P.O. Box 19024
Seattle, WA 98109-1024

E-mail: hpages at fhcrc.org
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