Thanks Mike - precisely what i was after. While this is a perfectly acceptable solution I wondered whether, following Mauro's suggestion, it was worth opening an issue in any case because it seems like it be nice to be able to link indexes in array comprehensions in a similar way to for-loops. Views?
On Monday, 21 September 2015 09:49:57 UTC+1, Michael Hatherly wrote: > > MyArray = [[zeros(Int, k) for n = 1:binomial(J, k)] for k = 1:K] > > seems to do what you want I think. Using 2 nested 1-d comprehensions > instead of a single 2-d comprehension. > > — Mike > > On Monday, 21 September 2015 10:37:06 UTC+2, Alan Crawford wrote: >> >> >> Thanks Tomas. If I do: >> >> Y = [Array(Int64,n) for n in map(k -> binomial(J,k), 1:K)] >> >> Then Y[1] gives the desired result (i.e. Y[1][k] is a length 1 vector). >> However, the issue for Y[2] and above. For example, if I do Y[2][k] where >> k∈[1,binomial(J,2)] >> then i get a length 1 vector, whereas I would like length 2 vector. >> Similarly for Y[3][k] I would like a length 3 vector. >> >> >> On Monday, 21 September 2015 09:23:56 UTC+1, Tomas Lycken wrote: >>> >>> Ah. >>> >>> Maybe [Array(Int64,n) for n in map(k -> binomial(J,k), 1:K)] is what >>> you’re looking for? >>> >>> // T >>> >>> On Monday, September 21, 2015 at 10:18:31 AM UTC+2, Alan Crawford wrote: >>> >>> The lower case k is intentional. I didn't want such a 'large' array as >>>> the one created when I use K because large parts of that array would be >>>> redundant. Ideally, I want this array to be as small as possible, >>>> especially since J and K might be quite a bit larger than in the example. >>>> >>>> On Monday, 21 September 2015 09:13:53 UTC+1, Tomas Lycken wrote: >>>>> >>>>> Are you sure that’s not just a typo between k and K (note the case >>>>> difference)? >>>>> >>>>> This works for me: >>>>> >>>>> J=10 >>>>> K=3 >>>>> MyArray = [Array(Int64,k) for k in 1:K, n in 1:binomial(J,K)] >>>>> >>>>> // T >>>>> >>>>> On Monday, September 21, 2015 at 10:08:13 AM UTC+2, Alan Crawford >>>>> wrote: >>>>> >>>>> Hi, >>>>>> >>>>>> I'd like to be able to define an array of vectors where the number of >>>>>> vectors in the array is linked to the length of the vector. For example, >>>>>> I >>>>>> want to be define an array with say 10 scalars, 45 length 2 vectors, 120 >>>>>> length 3 vectors, .... and so on. Intuitively, I thought the following >>>>>> code >>>>>> might achieve this: >>>>>> >>>>>> J=10 >>>>>> K=3 >>>>>> MyArray = [Array(Int64,k) for k in 1:K, n in 1:binomial(J,k)] >>>>>> >>>>>> >>>>>> However, it seems i cannot use k to define the number of element >>>>>> indexed by n. >>>>>> >>>>>> I was wondering if anyone knew how to create the desired array? >>>>>> >>>>>> Thanks >>>>>> Alan >>>>>> >>>>> >>>>> >>>> >>> >>
