Stavros Macrakis wrote
[...]
programming languages (including R). I don't know whether R's sum function
uses this technique or some other (e.g. Kahan summation), but it does manage
to give higher precision than summation with individual arithmetic
operators:
sum(c(2^63,1,-2^63)) => 1
not if the arguments are passed as separate elements in ...:
x = c(2^63, 1, -2^63)
sum(x)
# 1
do.call(sum, as.list(x))
# 0
y = 1:3
sum(y)
# 6
do.call(sum, as.list(y))
# 6
vQ
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