[R] Error in (function (cl, name, valueClass) :

Hello�� I have error in running the program: Any hint or help will be appreciated! Thanks in advance! Yue Error in (function (cl, name, valueClass) : assignment of an object of class ��numeric�� is not valid for @��Dim�� in an object of class ��dgTMatrix��; is(value, "integer") is not

Re: [R] choose(n, k) as n approaches k

On 14/01/2020 10:50 a.m., peter dalgaard wrote: On 14 Jan 2020, at 16:21 , Duncan Murdoch wrote: On 14/01/2020 10:07 a.m., peter dalgaard wrote: Yep, that looks wrong (probably want to continue discussion over on R-devel) I think the culprit is here (in src/nmath/choose.c) if (k <

[R] choose(n, k) as n approaches k

This struck me as incorrect: > choose(3.99, 4) [1] 0.979 > choose(3.999, 4) [1] 0 > choose(4, 4) [1] 1 > choose(4.001, 4) [1] 4 > choose(4.01, 4) [1] 1.02 Should base::choose(n, k) check whether n is within machine precision of k and return 1? Thanks, Erik ***

Re: [R] choose(n, k) as n approaches k

On 13/01/2020 6:33 p.m., Wright, Erik Scott wrote: This struck me as incorrect: choose(3.99, 4) [1] 0.979 choose(3.999, 4) [1] 0 choose(4, 4) [1] 1 choose(4.001, 4) [1] 4 choose(4.01, 4) [1] 1.02 Should base::choose(n, k) check whether n is within machine

Re: [R] choose(n, k) as n approaches k

On 14/01/2020 10:07 a.m., peter dalgaard wrote: Yep, that looks wrong (probably want to continue discussion over on R-devel) I think the culprit is here (in src/nmath/choose.c) if (k < k_small_max) { int j; if(n-k < k && n >= 0 && R_IS_INT(n)) k = n-k; /* <- Symmetry

Re: [R] choose(n, k) as n approaches k

> On 14 Jan 2020, at 16:21 , Duncan Murdoch wrote: > > On 14/01/2020 10:07 a.m., peter dalgaard wrote: >> Yep, that looks wrong (probably want to continue discussion over on R-devel) >> I think the culprit is here (in src/nmath/choose.c) >> if (k < k_small_max) { >> int j; >>

Re: [R] choose(n, k) as n approaches k

Yep, that looks wrong (probably want to continue discussion over on R-devel) I think the culprit is here (in src/nmath/choose.c) if (k < k_small_max) { int j; if(n-k < k && n >= 0 && R_IS_INT(n)) k = n-k; /* <- Symmetry */ if (k < 0) return 0.; if (k == 0)

Re: [R] choose(n, k) as n approaches k

OK, I see what you mean. But in those cases, we don't get the catastrophic failures from the if (k < 0) return 0.; if (k == 0) return 1.; /* else: k >= 1 */ part, because at that point k is sure to be integer, possibly after rounding. It is when n-k is approximately

Re: [R] [Rd] choose(n, k) as n approaches k

At the risk of throwing oil on a fire. If we are talking about fractional values of choose() doesn't it make sense to look to the gamma function for the correct analytic continuation? In particular k<0 may not imply the function should evaluate to zero until we get k<=-1. Example: ``` r

Re: [R] choose(n, k) as n approaches k

Um, n(n-1)(n-2)...(n-k+1)/factorial(k), of course, but I think the argument still holds. Also, note that there are overflow conditions involved with computing n(n-1)(n-2)...(n-k+1)/factorial(k) as written, so it is computed in a loop with alternating multiply and divide steps. This

Re: [R] Subset a data frame with specific date

Hi Bert I sometimes use indexing with "which" too, depends on desired result, especially with data frames. x <- 1:10 x[5:6] <- NA > xd <- data.frame(x, y=rnorm(10)) > xd[xd$x>3,] x y 4 4 -1.5086790 NA NA NA NA.1 NA NA 7 7 -0.2302614 8 8 -0.1660547 9