Could someone please explain the following? I did check bug reports, but did not recognize the issue there. I am reluctant to call it a bug, as it is much more likely my misunderstanding. Ergo my request for clarification: ## As expected:> lapply(1:3, rnorm, n = 3)[[1]] [1] 2.481575 1.998182 1.312786 [[2]] [1] 2.858383 1.827863 1.699015 [[3]] [1] 1.821910 2.530091 3.995677 ## Unexpected by me:> lapply(1:3, runif, n = 3)[[1]] [1] 1 1 1 [[2]] [1] NaN NaN NaN [[3]] [1] NaN NaN NaN Warning messages: 1: In FUN(X[[i]], ...) : NAs produced 2: In FUN(X[[i]], ...) : NAs produced ## But note, as expected:> lapply(1:3, function(x)runif(3))[[1]] [1] 0.2950459 0.8490556 0.4303680 [[2]] [1] 0.5961144 0.5330914 0.2363679 [[3]] [1] 0.8079495 0.1431838 0.3671915 Many thanks for any clarification. -- Bert [[alternative HTML version deleted]]

Hi Bert, On Tue, Nov 14, 2017 at 8:11 PM, Bert Gunter <bgunter.4567 at gmail.com> wrote:> Could someone please explain the following? I did check bug reports, but > did not recognize the issue there. I am reluctant to call it a bug, as it > is much more likely my misunderstanding. Ergo my request for clarification: > > ## As expected: > >> lapply(1:3, rnorm, n = 3) > [[1]] > [1] 2.481575 1.998182 1.312786 > > [[2]] > [1] 2.858383 1.827863 1.699015 > > [[3]] > [1] 1.821910 2.530091 3.995677 >Exactly what expectation do you imagine the above is consistent with? Does> lapply(100*(1:3), rnorm, n = 3)[[1]] [1] 100.35425 99.29429 98.69429 [[2]] [1] 198.2963 201.1031 201.1077 [[3]] [1] 299.7012 298.3700 298.0684 change your assessment?> > ## Unexpected by me: > >> lapply(1:3, runif, n = 3) > [[1]] > [1] 1 1 1 > > [[2]] > [1] NaN NaN NaN > > [[3]] > [1] NaN NaN NaN > > Warning messages: > 1: In FUN(X[[i]], ...) : NAs produced > 2: In FUN(X[[i]], ...) : NAs producedThe first argument to runif is named 'n'. Thus, lapply(1:3, runif) means roughly list(runif(n = 1), runif(n = 2), runif(n = 3)) But you specify than lapply(1:3, runif, n = 3). Since the first argument ('n') is already specified, the X values from lapply get "pushed" to the second argument. That is, lapply(1:3, runif, n = 3) means roughly list(runif(n = 3, min = 1), runif(n = 3, min = 2), runif(n = 3, min = 3)) Note that this is exactly the same thing that happens with lapply(1:3, rnorm, n = 3), though it becomes more obvious with lapply(100*(1:3), rnorm, n = 3) That is, lapply(1:3, rnorm, n = 3) means roughly list(rnorm(n = 3, mean = 1), rnorm(n = 3, mean = 2), rnorm(n = 3, mean = 3))> > > ## But note, as expected: > >> lapply(1:3, function(x)runif(3)) > [[1]] > [1] 0.2950459 0.8490556 0.4303680 > > [[2]] > [1] 0.5961144 0.5330914 0.2363679 > > [[3]] > [1] 0.8079495 0.1431838 0.3671915Sure, because you never use x in the body of your anonymous function. As a final note, what you seem to expect can be achieved with replicate(3, rnorm(n = 3), simplify = FALSE) and replicate(3, runif(n = 3), simplify = FALSE) Best, Ista> > > > Many thanks for any clarification. > > -- Bert > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.

Your lapply is making the call runif(n=3, min=i) for i in 1:3. That runif's 3 argument is 'max', with default value 1 so that is equivalent to calling runif(n=3, min=i, max=1) When i>max, outside the domain of the family of uniform distributions, runif returns NaN's. Bill Dunlap TIBCO Software wdunlap tibco.com On Tue, Nov 14, 2017 at 5:11 PM, Bert Gunter <bgunter.4567 at gmail.com> wrote:> Could someone please explain the following? I did check bug reports, but > did not recognize the issue there. I am reluctant to call it a bug, as it > is much more likely my misunderstanding. Ergo my request for clarification: > > ## As expected: > > > lapply(1:3, rnorm, n = 3) > [[1]] > [1] 2.481575 1.998182 1.312786 > > [[2]] > [1] 2.858383 1.827863 1.699015 > > [[3]] > [1] 1.821910 2.530091 3.995677 > > > ## Unexpected by me: > > > lapply(1:3, runif, n = 3) > [[1]] > [1] 1 1 1 > > [[2]] > [1] NaN NaN NaN > > [[3]] > [1] NaN NaN NaN > > Warning messages: > 1: In FUN(X[[i]], ...) : NAs produced > 2: In FUN(X[[i]], ...) : NAs produced > > > ## But note, as expected: > > > lapply(1:3, function(x)runif(3)) > [[1]] > [1] 0.2950459 0.8490556 0.4303680 > > [[2]] > [1] 0.5961144 0.5330914 0.2363679 > > [[3]] > [1] 0.8079495 0.1431838 0.3671915 > > > > Many thanks for any clarification. > > -- Bert > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/ > posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >[[alternative HTML version deleted]]