Calculate sum(x^2)
, but faster when the number of
elements exceeds 1000.
Examples
x <- rnorm(10000)
sumsquared(x)
#> [1] 9876.546
# Compare speed
microbenchmark::microbenchmark(
cpp = {sumsquared(x)},
r = {sum(x^2)}
)
#> Unit: microseconds
#> expr min lq mean median uq max neval
#> cpp 37.811 37.9260 38.66450 38.062 38.2870 53.480 100
#> r 24.857 25.3025 26.30919 25.598 26.8055 39.263 100