OSBRAC also not working

ho_basis.jl

@@ -1,7 +1,7 @@
 using SparseArrays
-using NuclearToolkit
 using SpecialFunctions
 include("helper.jl")
+include("osbrackets.jl")
 
 # Gaussian potentials in HO space
 inv_factorial(n) = Iterators.prod(inv.(1:n))
@@ -36,7 +36,7 @@ function get_2p_basis(E_max)
     l2s = Int[]
 
     # E = 2*n1 + l1 + 2*n2 + l2
-    for E in 0 : 2*E_max
+    for E in 2*E_max : -2 : 0
         for n1 in 0 : E ÷ 2
             for n2 in 0 : (E - 2*n1) ÷ 2
                 for l1 in 0 : (E - 2*n1 - 2*n2)
@@ -84,15 +84,17 @@ function sp_V_matrix(V_l, ns, ls; mask=trues(length(ns),length(ns)), dtype=Float
 end
 
 function Moshinsky_transform(Es, n1s, l1s, n2s, l2s, Λ)
-    E_max = maximum(Es)
+    Emax = maximum(Es) ÷ 2      # TODO: Too many steps. Simplify.
-    j_max = 2 * E_max + 1
+
-    l_max = j_max
+    ul1s = unique(l1s)
-    to = 0 # unused
+    ul2s = unique(l2s)
-    
+    BRACs = Matrix{Array}(undef, length(ul1s), length(ul2s))
-    dtri = NuclearToolkit.prep_dtri(l_max + 1);
+    for l1 in ul1s
-    dcgm0 = NuclearToolkit.prep_dcgm0(l_max);
+        for l2 in ul2s
-    d6j = nothing # NuclearToolkit.prep_d6j_int(E_max, j_max, to);
+            BRACs[l1, l2] = cal_BRAC(Emax, Λ, l1, l2)
-    
+        end
+    end
+
     mat = spzeros(length(Es), length(Es))
     s = hcat(Es, n1s, l1s, n2s, l2s)
     for idx in CartesianIndices(mat)
@@ -100,7 +102,8 @@ function Moshinsky_transform(Es, n1s, l1s, n2s, l2s, Λ)
         (Elhs, N, L, n, l) = s[i, :]
         (Erhs, n1, l1, n2, l2) = s[j, :]
         if Elhs == Erhs
-            mat[i, j] = NuclearToolkit.HObracket_d6j(N, L, n, l, n1, l1, n2, l2, Λ, 1.0, dtri, dcgm0, d6j)
+            phase = (-1)^(N + n + n1 + n2)
+            mat[i, j] = phase * get_bracket(BRACs[l1, l2], Emax, Λ, N, L, n, l, n1, n2)
         end
     end
 

osbrackets.jl

@@ -0,0 +1,42 @@
+# compile using
+# gfortran -shared -fPIC osbrac.f90 -o osbrac.so
+# gfortran -shared -fPIC allosbrac.f90 -o allosbrac.so
+
+using Libdl
+
+function cal_BRAC(Emax, Λ, l1, l2)
+    ϵ = (2 * Emax - Λ) % 2
+    N = (l1 - l2 + Λ - ϵ) ÷ 2
+    M = (l1 + l2 - Λ - ϵ) ÷ 2
+    L = Λ
+    NQMAX = 2 * Emax
+    CO = 1/sqrt(2)
+    SI = 1/sqrt(2)
+    FIRSTCALL = true
+    # dimensions BRAC(0:L,0:(NQMAX-L)/2,0:(NQMAX-L)/2,0:(NQMAX-L)/2,0:(NQMAX-L)/2)
+    BRAC = zeros(Float64, 1 + L, 1 + (NQMAX - L) ÷ 2, 1 + (NQMAX - L) ÷ 2, 1 + (NQMAX - L) ÷ 2, 1 + (NQMAX - L) ÷ 2)
+
+    lib = Libdl.dlopen("OSBRACKETS/osbrac.so") # Open the library explicitly.
+    sym = Libdl.dlsym(lib, :osbrac_)   # Get a symbol for the function to call.
+    # call signature OSBRAC(N,M,L,NQMAX,CO,SI,FIRSTCALL,BRAC)
+    @ccall $sym(N::Ref{Int32},M::Ref{Int32},L::Ref{Int32},NQMAX::Ref{Int32},CO::Ref{Float64},SI::Ref{Float64},FIRSTCALL::Ref{UInt8},BRAC::Ptr{Array{Float64}})::Cvoid
+    Libd.dlclose(lib)
+
+    return BRAC
+end
+
+function get_bracket(BRAC, Emax, Λ, n1′, l1′, n2′, l2′, n1, n2)
+    ϵ = (2 * Emax - Λ) % 2
+    NP = (l1′ - l2′ + Λ - ϵ) ÷ 2
+    N1P = n1′
+    MP = (l1′ + l2′ - Λ - ϵ) ÷ 2
+    N1 = n1
+    N2 = n2
+    N2P = n2′
+    if MP+N1P+N2P == M+N1+N2
+        # BRAC(NP,N1P,MP,N1,N2)
+        return BRAC[1 + NP, 1 + N1P, 1 + MP, 1 + N1, 1 + N2]
+    else
+        return 0
+    end
+end