ViralBShah
commented
10 years ago Sparse indexing and concatenation need to be fully revisited. At least someone is using these now!
Closed joachimdahl closed 10 years ago
ViralBShah
commented
10 years ago Sparse indexing and concatenation need to be fully revisited. At least someone is using these now!
joachimdahl
commented
10 years ago Sorry, my example was buggy. I created the compressed structure directly, and the indices were not sorted...
ViralBShah
commented
10 years ago Of course - in such a case you should use sparse to construct the sparse matrix.
joachimdahl
commented
10 years ago I agree... I had a compressed column-storage from C (unsorted), which I was importing...
On Wed, Nov 27, 2013 at 9:50 AM, Viral B. Shah notifications@github.comwrote:
Of course - in such a case you should use sparse to construct the sparse matrix.
— Reply to this email directly or view it on GitHubhttps://github.com/JuliaLang/julia/issues/4938#issuecomment-29368411 .
ViralBShah
commented
10 years ago You can do a double transpose if you have an unsorted SparseMatrixCSC and you will end up with a sorted one.
joachimdahl
commented
10 years ago thanks, that actually ended up being my solution.
Let me congratulate with the efforts you have made so far with Julia. I have used it for a few weeks, and love everything about it. Before I used Python or Matlab to prototype numerical algorithms we work on at MOSEK, and Julia seems to be the perfect match for me.
On Wed, Nov 27, 2013 at 10:07 AM, Viral B. Shah notifications@github.comwrote:
You can do a double transpose if you have an unsorted SparseMatrixCSC and you will end up with a sorted one.
— Reply to this email directly or view it on GitHubhttps://github.com/JuliaLang/julia/issues/4938#issuecomment-29369295 .
ViralBShah
commented
10 years ago Thanks. What is MOSEK? Great to see a pull request from you too, and all the stuff you are asking for is good stuff.
ViralBShah
commented
10 years ago Is this www.mosek.com? In which case, I must Cc: @iainnz and @mlubin.
IainNZ
commented
10 years ago Glad to see Julia making a splash in the OR world!
joachimdahl
commented
10 years ago Yes, we specialize in interior-point solvers for conic optimization.
On Wed, Nov 27, 2013 at 2:54 PM, Iain Dunning notifications@github.comwrote:
Glad to see Julia making a splash in the OR world!
— Reply to this email directly or view it on GitHubhttps://github.com/JuliaLang/julia/issues/4938#issuecomment-29385574 .
I noticed the following bug concatenating sparse matrices. I could not reproduce it using simpler matrices...
julia> A=SparseMatrixCSC(6,3,[1,2,3,4],[6,1,6],[-1.0,-1.0,1.0]) 6x3 sparse matrix with 3 Float64 nonzeros: [6, 1] = -1.0 [1, 2] = -1.0 [6, 3] = 1.0
julia> B=SparseMatrixCSC(6,5,[2,6,10,14,18,23], [6,1,2,3,6,1,4,5,6,1,4,5,6,1,2,3,6,1,2,3,4,5], [1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0]) 6x5 sparse matrix with 22 Float64 nonzeros: [1, 1] = 1.0 [2, 1] = 1.0 [3, 1] = 1.0 [6, 1] = 1.0 [1, 2] = 1.0 [4, 2] = 1.0 [5, 2] = 1.0 [6, 2] = 1.0 [1, 3] = 1.0 [4, 3] = 1.0 [5, 3] = 1.0 [6, 3] = 1.0 [1, 4] = 1.0 [2, 4] = 1.0 [3, 4] = 1.0 [6, 4] = 1.0 [1, 5] = 1.0 [2, 5] = 1.0 [3, 5] = 1.0 [4, 5] = 1.0 [5, 5] = 1.0
julia> [A B] ERROR: tried to assign 23 elements to 22 destinations in error at error.jl:21 in setindex! at array.jl:435 in hcat at sparse/sparsematrix.jl:1265