Thanks a lot - this really cleared some thing in my head! Using the dims argument as "dims..." had not occurred to me. Can you explain how the dots work (or point to reference)?
I realized now that the part about the C matrix was oversimplified here, but now that I seem to have befriended the tuples it works :-) (That Kronecker question was stupid of me; sorry :-)) Thanks again! On Tuesday, November 11, 2014 4:31:21 PM UTC+1, David Gonzales wrote: > > Reworked some of the construction to be more succint: > > function example(dims...) > A = [zeros(2^l*[dims...]...) for l = 0:2] > @show A > > > J = [1 3 ; 2 4] > I = kron(J, ones(Int,2,2)) > K = rand(4) > B = K[I] > @show B > > > C = zeros( dims... ) > @show C > > nothing > end > > > > This is running on version 0.4-dev+1307 > > On Tuesday, November 11, 2014 3:19:38 PM UTC+2, Robert DJ wrote: >> >> Hi >> >> I've run into some array issues that I suspect are quite easy, but I >> haven't found answers on Uncle Google or in the docs. >> >> In the example below I would like to do the following (more elegant): >> >> - Create the array of arrays A where the size of the inner arrays are >> determined by the input 'dims...'. >> Creating the D array seems cumbersome. >> >> - Create the array B with a block structure defined by the array I. >> The Kronecker product is automatically a Float even though both factors >> are Int's and Float doesn't seem to work as indices; is there a better way >> to circumvent this than ifloor? >> >> - repmath/reshape seems to like tuples, but not arrays as the new >> dimensions. >> Is there a way to convert between tuples and arrays? >> >> Thanks, >> >> Robert >> >> >> function example(dims...) >> D = Array(Int, 2) >> D[1] = dims[1] >> D[2] = dims[2] >> A = [zeros(2^l*D[1], 2^l*D[2]) for l = 0:2] >> # Not working: >> #A = [zeros(2^l*dims) for l = 0:2] >> >> J = [1 3 ; 2 4] >> I = ifloor(kron(J, ones(2,2))) >> K = rand(4) >> B = K[I] >> >> C = zeros( prod(D) ) >> C = reshape(C, dims) >> # Not working: >> #C = reshape(C, D) >> end >> >>
