fix return value for iterative layout

NEWS.md

@@ -0,0 +1,6 @@
+# NetworkLayout Release Notes
+
+## v0.4.11 Changelog
+- Fixes two bugs in the iteration scheme:
+  - The layout iterator returned the second-to-last layout; now it returns the final positions after full iteration.
+  - Iterative layouts computed `iterations` layouts, including the initial guess. Now `iterations` describes the number of actual *iterations*, and the layout iterator returns at most `iterations + 1` layouts.

src/NetworkLayout.jl

@@ -79,13 +79,9 @@ end
 
 function layout(alg::IterativeLayout, adj_matrix::AbstractMatrix)
     assertsquare(adj_matrix)
-    iter = LayoutIterator(alg, adj_matrix)
-    next = Base.iterate(iter)
-    pos = next[1]
-    while next !== nothing
-        (item, state) = next
-        next = Base.iterate(iter, state)
-        pos = next !== nothing ? item : pos
+    local pos
+    for item in LayoutIterator(alg, adj_matrix)
+        pos = item
     end
     return pos
 end

src/sfdp.jl

@@ -85,7 +85,7 @@ function Base.iterate(iter::LayoutIterator{<:SFDP}, state)
     K, C, tol = algo.K, algo.C, algo.tol
 
     # stop if stopflag (tol reached) or nr of iterations reached
-    if iter >= algo.iterations || stopflag
+    if iter > algo.iterations || stopflag
         return nothing
     end
 

src/spring.jl

@@ -81,7 +81,7 @@ end
 function Base.iterate(iter::LayoutIterator{<:Spring}, state)
     algo, adj_matrix = iter.algorithm, iter.adj_matrix
     iteration, old_pos, pin, rng = state
-    iteration >= algo.iterations && return nothing
+    iteration > algo.iterations && return nothing
 
     # The optimal distance bewteen vertices
     N = size(adj_matrix, 1)

src/stress.jl

@@ -153,7 +153,7 @@ function Base.iterate(iter::LayoutIterator{<:Stress{Dim,Ptype}}, state) where {D
     algo, δ = iter.algorithm, iter.adj_matrix
     i, oldstress, oldpos, weights, distances, pinvLw, maxiter, pin, stopflag = state
 
-    if i >= maxiter || stopflag
+    if i > maxiter || stopflag
         return nothing
     end
 

test/runtests.jl

@@ -46,8 +46,9 @@ jagmesh_adj = jagmesh()
                 for p in it
                     push!(vec, p)
                 end
-                @test length(vec) == l
-                @test length(unique!(vec)) == l
+                @test length(vec) == l + 1
+                @test it.algorithm(adj_matrix) == last(vec)
+                @test length(unique!(vec)) == l + 1
             end
         end
 
@@ -103,8 +104,9 @@ jagmesh_adj = jagmesh()
                 for p in it
                     push!(vec, p)
                 end
-                @test length(vec) == l
-                @test length(unique!(vec)) == l
+                @test length(vec) == l + 1
+                @test it.algorithm(adj_matrix) == last(vec)
+                @test length(unique!(vec)) == l + 1
             end
         end
 
@@ -211,8 +213,9 @@ jagmesh_adj = jagmesh()
                 for p in it
                     push!(vec, p)
                 end
-                @test length(vec) == l
-                @test length(unique!(vec)) == l
+                @test length(vec) == l + 1
+                @test it.algorithm(adj_matrix) == last(vec)
+                @test length(unique!(vec)) == l + 1
             end
         end
 
@@ -472,7 +475,7 @@ jagmesh_adj = jagmesh()
             positions :: Vector{Point{Dim, Ptype}}
         end
         NetworkLayout.layout(algo::Manual, ::AbstractMatrix) = copy(algo.positions)
-        
+
         g = Graph(2); add_edge!(g, 1, 2)
         pos = Align(Manual([Point2f(1, 2), Point2f(2, 3)]), 0.0)(g)
         @test all(r->abs(r[2])<1e-12, pos)