Add move_marg

Author: sebastiendesignolle

src/utils.jl

@@ -1108,3 +1108,15 @@ function shrinking_squared(vecs::Vector{<:AbstractMatrix{T}}; verbose = true) wh
     return eta2
 end
 export shrinking_squared
+
+"""
+    move_marg(FC::AbstractArray, sense::Int = -1)
+
+Change convention for the placement of marginals.
+By default, converts from first to last index.
+If `sense=1`, convert back from last to first index.
+"""
+function move_marg(FC::AbstractArray{T, N}, sense = -1) where {T, N}
+    return circshift(FC, ntuple(i -> sense, Val(N)))
+end
+export move_marg

test/runtests.jl

@@ -70,7 +70,7 @@ end
 
 @testset "Testing Bell-Frank-Wolfe with d=2, N=2, and cor/marg matrices   " begin
     # using the exact LMO at the end
-    p = circshift(tensor_correlation(state_phiplus(), HQVNB17_mes(3), 2; marg=true), (-1, -1))
+    p = move_marg(tensor_correlation(state_phiplus(), HQVNB17_mes(3), 2; marg=true))
     @test abs(bell_frank_wolfe(p; marg=true, mode_last=1)[3] - 0.613691) < 1e-5
     # with warm start
     active_set = bell_frank_wolfe(p; marg=true, max_iteration=10)[5]
@@ -83,9 +83,9 @@ end
     # HQVNB17 with symmetry
     @test abs(bell_frank_wolfe(p; marg=true)[3] - 0.613691) < 1e-5
 
-    p = circshift(tensor_correlation(state_phiplus(), HQVNB17_mes(5), 2; marg=true), (-1, -1))
+    p = move_marg(tensor_correlation(state_phiplus(), HQVNB17_mes(5), 2; marg=true))
     @test abs(bell_frank_wolfe(p; marg=true)[3] - 5.69) < 1e-1
-    #  @test abs(bell_frank_wolfe(circshift(tensor_correlation(state_phiplus(), HQVNB17_mes(7), 2; marg=true), (-1, -1)); marg=true)[3] - 23.02) < 1e-1
+    #  @test abs(bell_frank_wolfe(move_marg(tensor_correlation(state_phiplus(), HQVNB17_mes(7), 2; marg=true)); marg=true)[3] - 23.02) < 1e-1
 end
 
 @testset "Testing Bell-Frank-Wolfe with d=2, N=3, and correlation tensors " begin