search for: mechnaism

...>> system.time(for (i in 1:10000) subset_ROW4(arr,seq(1,length=10,by=100),TRUE)) >> >> and with >> >> system.time(for (i in 1:10000) subset_ROW4(arr,seq(1,length=10,by=100),FALSE)) > > I think that's because you used a relatively low precision timing > mechnaism, and included the index generation in the timing. I see: > > arr <- array(rnorm(2^22),c(2^10,4,4,4)) > i <- seq(1,length = 10, by = 100) > > bench::mark( > arr[i, TRUE, TRUE, TRUE], > arr[i, , , ] > ) > #> # A tibble: 2 x 1 > #> expression min...

> On Jun 8, 2018, at 10:37 AM, Herv? Pag?s <hpages at fredhutch.org> wrote: > > Also the TRUEs cause problems if some dimensions are 0: > > > matrix(raw(0), nrow=5, ncol=0)[1:3 , TRUE] > Error in matrix(raw(0), nrow = 5, ncol = 0)[1:3, TRUE] : > (subscript) logical subscript too long OK. But this is easy enough to handle. > > H. > > On

...> I get identical times with > > system.time(for (i in 1:10000) subset_ROW4(arr,seq(1,length=10,by=100),TRUE)) > > and with > > system.time(for (i in 1:10000) subset_ROW4(arr,seq(1,length=10,by=100),FALSE)) I think that's because you used a relatively low precision timing mechnaism, and included the index generation in the timing. I see: arr <- array(rnorm(2^22),c(2^10,4,4,4)) i <- seq(1,length = 10, by = 100) bench::mark( arr[i, TRUE, TRUE, TRUE], arr[i, , , ] ) #> # A tibble: 2 x 1 #> expression min mean median max n_gc #> <chr&...

...(i in 1:10000) subset_ROW4(arr,seq(1,length=10,by=100),TRUE)) >>> >>> and with >>> >>> system.time(for (i in 1:10000) subset_ROW4(arr,seq(1,length=10,by=100),FALSE)) >> >> I think that's because you used a relatively low precision timing >> mechnaism, and included the index generation in the timing. I see: >> >> arr <- array(rnorm(2^22),c(2^10,4,4,4)) >> i <- seq(1,length = 10, by = 100) >> >> bench::mark( >> arr[i, TRUE, TRUE, TRUE], >> arr[i, , , ] >> ) >> #> # A tibble: 2 x 1 &...