DArray roadmap

### object identity and equality
- [x] copy
- [x] deepcopy (aliases)
- [ ] hash (works but through the `AbstractArray` fallback)
- [x] identity
- [x] isbits
- [ ] isequal (works but through the `AbstractArray` fallback)
- [x] isimmutable
- [ ] lexless (works but through the `AbstractArray` fallback. It just requires `lexcmp`)
- [ ] lexcmp (works but through the `AbstractArray` fallback)
- [x] object_id
- [x] sizeof
### collections
- [x] all!
- [x] all
- [x] any!
- [x] any
- ~~collect~~
- [ ] contains (works but through the `AbstractArray` fallback)
- [x] count
- [ ] deleteat!
- [x] eltype
- [ ] empty!
- [x] endof
- [ ] filter!
- [ ] filter
- [ ] foldl (works but through the `AbstractArray` fallback)
- [ ] foldr (works but through the `AbstractArray` fallback)
- [x] get
- [ ] get!
- [x] getindex
- [ ] in (works but through the `AbstractArray` fallback)
- [ ] intersect!
- [ ] intersect (works but through the `AbstractArray` fallback)
- [x] isempty
- [ ] issubset (works but through the `AbstractArray` fallback)
- [x] length
- [x] map!
- [x] map
- [ ] mapfoldl (works but through the `AbstractArray` fallback)
- [ ] mapfoldr (works but through the `AbstractArray` fallback)
- [x] mapreduce
- [x] mapreducedim
- [x] reduce
- [ ] setdiff (works but through the `AbstractArray` fallback)
- [ ] setindex!
- [x] similar
- ~~sizehint!~~ (Probably doesn't make sense)
- [ ] splice!
- [ ] symdiff (works but through the `AbstractArray` fallback)
- [ ] union (works but through the `AbstractArray` fallback)
- [ ] unique (works but through the `AbstractArray` fallback)
### iteration (works but through the `AbstractArray` fallback. This requires some care to work well)
- [ ] done
- [ ] enumerate
- [ ] next
- [ ] start
- [ ] zip
- [ ] rest
- [ ] countfrom
- [ ] take
- [ ] drop
- [ ] cycle
- [ ] repeated
### arrays
- [ ] broadcast!
- [x] broadcast
- [ ] cat
- [x] checkbounds
- [ ] circshift
- [ ] conj!
- [x] copy!
- [ ] cummax
- [ ] cummin
- [ ] cumprod
- [ ] cumprod!
- [ ] cumsum
- [ ] cumsum!
- [ ] cumsum_kbn
- [x] eachindex
- [ ] extrema (works but through the `AbstractArray` fallback)
- [x] fill!
- [ ] find (works but through the `AbstractArray` fallback)
- [ ] findfirst (works but through the `AbstractArray` fallback)
- [ ] findlast (works but through the `AbstractArray` fallback)
- [ ] findin (works but through the `AbstractArray` fallback)
- [ ] findmax (works but through the `AbstractArray` fallback)
- [ ] findmin (works but through the `AbstractArray` fallback)
- [ ] findn (works but through the `AbstractArray` fallback)
- [ ] findnext (works but through the `AbstractArray` fallback)
- [ ] findprev (works but through the `AbstractArray` fallback)
- [ ] findnz (works but through the `AbstractArray` fallback)
- [ ] first (works but through the `AbstractArray` fallback)
- [ ] flipdim
- ~~gradient~~ (will probably go away in base)
- [ ] hcat
- [ ] hvcat
- [x] ind2sub
- [ ] indexin (works but through the `AbstractArray` fallback)
- [ ] indmax (works but through the `AbstractArray` fallback)
- [ ] indmin (works but through the `AbstractArray` fallback)
- [ ] invperm
- [ ] ipermute!
- [ ] ipermutedims
- [ ] isperm (works but through the `AbstractArray` fallback)
- [ ] issorted (works but through the `AbstractArray` fallback)
- [ ] last (works but through the `AbstractArray` fallback)
- [ ] linspace (`dlinspace`?)
- [ ] logspace (`dlogspace`?)
- [x] mapslices
- [ ] max (works but through the `AbstractArray` fallback)
- [x] maxabs
- [ ] maxabs!
- [ ] maximum!
- [x] maximum
- [ ] min (works but through the `AbstractArray` fallback)
- [x] minabs
- [ ] minabs!
- [ ] minimum!
- [x] minimum
- [ ] minmax
- [x] ndims
- [x] nnz
- [ ] nonzeros
- [x] countnz
- [x] ones
- [x] parent
- [x] parentindexes
- [ ] permute!
- [ ] permutedims
- [ ] permutedims!
- [ ] prod!
- [x] prod
- [x] promote_shape
- [ ] randcycle (`drandcycle`)
- [ ] randperm (`drandperm`)
- [ ] randsubseq! (works but through the `AbstractArray` fallback)
- [ ] randsubseq (works but through the `AbstractArray` fallback)
- [x] reducedim
- [ ] repmat
- [x] reshape
- [ ] reverse!
- [ ] reverse
- [ ] rot180
- [ ] rotl90
- [ ] rotr90
- [ ] searchsorted (works but through the `AbstractArray` fallback)
- [ ] searchsortedfirst (works but through the `AbstractArray` fallback)
- [ ] searchsortedlast (works but through the `AbstractArray` fallback)
- [ ] select!
- [ ] select
- [ ] shuffle
- [ ] shuffle!
- [x] size
- [x] view
- [ ] slicedim
- [ ] sort!
- [x] sort
- [ ] sortcols
- [ ] sortperm (works but through the `AbstractArray` fallback)
- [ ] sortperm!
- [ ] sortrows
- [ ] squeeze
- [ ] step
- [ ] stride
- [ ] strides
- [ ] sub
- [ ] sub2ind
- [ ] sum!
- [x] sum
- [ ] sumabs!
- [x] sumabs
- [ ] sumabs2!
- [x] sumabs2
- [ ] sum_kbn
- [ ] vcat
- [ ] vec
- [x] zeros
### linear algebra
- [ ] bkfact!
- [ ] bkfact
- [ ] blas_set_num_threads
- [ ] blkdiag
- [ ] chol
- [ ] cholfact!
- [ ] cholfact
- [ ] cond
- [ ] condskeel
- [ ] cross
- [ ] ctranspose!
- [x] ctranspose
- [ ] det
- [ ] diag
- [ ] diagind
- [ ] diagm
- [ ] diff
- [ ] dot
- [ ] eig
- [ ] eigfact!
- [ ] eigfact
- [ ] eigmax
- [ ] eigmin
- [ ] eigs
- [ ] eigvals
- [ ] eigvals!
- [ ] eigvecs
- [ ] expm
- [ ] eye
- [ ] factorize
- [ ] givens
- [ ] hessfact!
- [ ] hessfact
- [ ] ishermitian
- [ ] isposdef!
- [ ] isposdef
- [ ] issym
- [ ] istril
- [ ] istriu
- [ ] kron
- [ ] ldltfact
- [ ] ldltfact!
- [ ] linreg
- [ ] logdet
- [ ] lu
- [ ] lufact!
- [ ] lufact
- [ ] lyap
- [ ] norm
- [ ] nullspace
- [ ] ordschur!
- [ ] ordschur
- [ ] peakflops
- [ ] pinv
- [ ] qr
- [ ] qrfact!
- [ ] qrfact
- [ ] rank
- [x] scale!
- [ ] scale
- [ ] schur
- [ ] schurfact!
- [ ] schurfact
- [ ] sqrtm
- [ ] svd
- [ ] svdfact!
- [ ] svdfact
- [ ] svds
- [ ] svdvals!
- [ ] svdvals
- [ ] sylvester
- [ ] trace
- [ ] transpose!
- [x] transpose
- [ ] tril!
- [ ] tril
- [ ] triu!
- [ ] triu
- [ ] vecnorm
### sparse
- [ ] etree
- [ ] full
- [ ] issparse
- [ ] sparse
- [ ] sparsevec
- [ ] spdiagm
- [ ] speye
- [ ] spones
- [ ] sprand
- [ ] sprandbool
- [ ] sprandn
- [ ] spzeros
- [ ] symperm
- [ ] rowvals
- [ ] nzrange
# Operators
- [x] !
- [x] !=
- [x] ≠
- [x] !==
- [x] ≡
- [x] ≢
- [x] *
- [x] +
- [x] -
- [ ] /
- [x] //
- [x] ==
- [ ] \
- [ ] ^
- [ ] A_ldiv_B!
- [ ] A_ldiv_Bc
- [ ] A_ldiv_Bt
- [ ] A_mul_B!
- [ ] A_mul_Bc
- [ ] A_mul_Bc!
- [ ] A_mul_Bt
- [ ] A_mul_Bt!
- [ ] A_rdiv_Bc
- [ ] A_rdiv_Bt
- [ ] Ac_ldiv_B
- [ ] Ac_ldiv_Bc
- [x] Ac_mul_B
- [x] Ac_mul_B!
- [ ] Ac_mul_Bc
- [ ] Ac_mul_Bc!
- [ ] Ac_rdiv_B
- [ ] Ac_rdiv_Bc
- [ ] At_ldiv_B
- [ ] At_ldiv_Bt
- [ ] At_mul_B
- [ ] At_mul_B!
- [ ] At_mul_Bt
- [ ] At_mul_Bt!
- [ ] At_rdiv_B
- [ ] At_rdiv_Bt
### random numbers
- [ ] rand!
- [x] rand
- [ ] randn!
- [x] randn
- [ ] randexp!
- [ ] randexp
- [ ] srand
- [ ] bitrand
### statistics
- [ ] cor
- [ ] cov
- [x] mean!
- [x] mean
- [ ] median!
- [x] median
- [ ] middle
- [ ] midpoints
- [ ] quantile!
- [ ] quantile
- [x] std
- [x] stdm
- [x] var
- [x] varm
### signal processing
- [ ] bfft!
- [ ] bfft
- [ ] brfft
- [ ] conv
- [ ] conv2
- [ ] dct!
- [ ] dct
- [ ] deconv
- [ ] fft!
- [ ] fft
- [ ] fftshift
- [ ] filt
- [ ] filt!
- [ ] idct!
- [ ] idct
- [ ] ifft!
- [ ] ifft
- [ ] ifftshift
- [ ] irfft
- [ ] plan_bfft!
- [ ] plan_bfft
- [ ] plan_brfft
- [ ] plan_dct!
- [ ] plan_dct
- [ ] plan_fft!
- [ ] plan_fft
- [ ] plan_idct!
- [ ] plan_idct
- [ ] plan_ifft!
- [ ] plan_ifft
- [ ] plan_irfft
- [ ] plan_rfft
- [ ] rfft
- [ ] xcorr

Update 30 September 2016 by @andreasnoack: I've removed all the scalar math and special functions. With the `.` syntax + `broadcast(x::DArray) = map(x)` they should work.

No files, tests, or entry points are named. Start by choosing one unchecked DArray operation and tracing its current AbstractArray fallback in the Julia implementation; done means the selected operation is implemented for DArray and its behavior is verified against the roadmap entry.

Do mô hình lập chỉ mục viết ra từ nội dung của issue.