add dcat and blkdiag, update tests and perf

base/abstractarray.jl

@@ -763,8 +763,9 @@ function typed_cat(T::Type, catdim::Integer, X...)
     C=cat_similar(X[1], T, catsize(n, catdim, N, X[1]))
     offset = 0
     for i = 1:length(X)
-        r = offset+catrange(catdim, X[i])
-        cat_fill!(C, catdim, r, X[i])
+        x = X[i]
+        r = offset+catrange(catdim, x)
+        cat_fill!(C, catdim, r, x)
         offset = last(r)
     end
     C
@@ -790,8 +791,7 @@ function typed_hvcat(T::Type, rows::(Int...), X...)
     k = 1
     N = catndims(X[k])
     for i = 2:length(X)
-        x = X[i]
-        Ni = catndims(x)
+        Ni = catndims(X[i])
         Ni > N && (k=i;N=Ni)
     end
 
@@ -818,7 +818,7 @@ end
 
 hvcat{T}(rows::(Int...), X::T...) = typed_hvcat(cattype(T), rows, X...)
 hvcat{T}(rows::(Int...), X::AbstractArray{T}...) = typed_hvcat(T, rows, X...)
-hvcat(rows::(Int...), X...) = typed_hcat(promote_cattypeof(X...), rows, X...)
+hvcat(rows::(Int...), X...) = typed_hvcat(promote_cattypeof(X...), rows, X...)
 
 function hvcat(nbc::Integer, A...)
     # nbc = # of block columns
@@ -830,6 +830,49 @@ function hvcat(nbc::Integer, A...)
     hvcat(ntuple(i->nbc, nbr), A...)
 end
 
+## dcat: cat along diagonals
+function typed_dcat(T::Type, catdims, X...)
+    dims = Int[d for d in catdims]
+    M = length(dims)
+    N = maximum(dims)
+    for i = 1:length(X)
+        N = max(N,catndims(X[i]))
+    end
+
+    catsizes = zeros(Int, N)
+    for i = 1:length(X)
+        x = X[i]
+        for j = 1:M
+            catdim = dims[j]
+            catsizes[catdim] += catlength(catdim,x)
+        end
+    end
+    for d = 1:N
+        catsizes[d] == 0 && (catsizes[d]=catlength(d,X[1]))
+    end
+    C=cat_similar(X[1], T, tuple(catsizes...))
+    M > 1 && fill!(C,zero(T))
+
+    offsets = zeros(Int, M)
+    catranges = [1:size(C,d) for d=1:N]
+    for i = 1:length(X)
+        x=X[i]
+        for j=1:M
+            catdim = dims[j]
+            catranges[catdim] = offsets[j] + (1:catlength(catdim, x))
+            offsets[j] = last(catranges[catdim])
+        end
+        C[catranges...] = x
+    end
+    C
+end
+
+dcat{T}(catdims, X::T...) = typed_dcat(cattype(T), catdims, X...)
+dcat{T}(catdims, X::AbstractArray{T}...) = typed_dcat(T, catdims, X...)
+dcat(catdims, X...) = typed_dcat(promote_cattypeof(X...), catdims, X...)
+
+blkdiag(X...) = dcat([1,2], X...)
+
 ## Reductions and scans ##
 
 function isequal(A::AbstractArray, B::AbstractArray)

base/exports.jl

@@ -502,6 +502,7 @@ export
 
 # arrays
     bitbroadcast,
+    blkdiag,
     broadcast!,
     broadcast!_function,
     broadcast,
@@ -523,6 +524,7 @@ export
     cumsum,
     cumsum!,
     cumsum_kbn,
+    dcat,
     eachindex,
     extrema,
     fill!,

test/arrayops.jl

@@ -82,9 +82,9 @@ tmp = zeros(Int,map(maximum,rng)...)
 tmp[rng...] = A[rng...]
 @test  tmp == cat(3,zeros(Int,2,3),[0 0 0; 0 47 52],zeros(Int,2,3),[0 0 0; 0 127 132])
 
-@test cat([1,2],1,2,3.,4.,5.) == diagm([1,2,3.,4.,5.])
+@test dcat([1,2],1,2,3.,4.,5.) == diagm([1,2,3.,4.,5.])
 blk = [1 2;3 4]
-tmp = cat([1,3],blk,blk)
+tmp = dcat([1,3],blk,blk)
 @test tmp[1:2,1:2,1] == blk
 @test tmp[1:2,1:2,2] == zero(blk)
 @test tmp[3:4,1:2,1] == zero(blk)