Add JuMP model for tetra

src/PureJuMP/tetra.jl

@@ -0,0 +1,75 @@
+# Minimize the sum of the inverse weighted mean ratio of the elements in a fixed–boundary
+# tetrahedral mesh by adjusting the locations of the free vertices.
+
+#  This is problem 19 in the COPS (Version 3) collection of 
+#   E. Dolan and J. More
+#   see "Benchmarking Optimization Software with COPS"
+#   Argonne National Labs Technical Report ANL/MCS-246 (2004)
+
+include("../../data/tetra.jl")
+export tetra
+
+function tetra(
+  x0 = xe_tetra,
+  TETS::Vector{Int64} = Tets_tetra,
+  Const::Vector{Int64} = Constants_tetra;
+  kwargs...,
+)
+  τ = 0.0
+  n = length(x0)
+  N = round(Int,n/3)
+  E = round(Int,length(TETS)/4)
+
+  lvar = -Inf * ones(n)
+  lvar[Const] = x0[Const]
+  lvar[Const.+N] = x0[Const.+N]
+  lvar[Const.+ 2*N] = x0[Const.+ 2*N]
+
+  uvar = Inf * ones(n)
+  uvar[Const] = x0[Const]
+  uvar[Const.+N] = x0[Const.+N]
+  uvar[Const.+ 2*N] = x0[Const.+ 2*N]
+
+  nlp = Model()
+
+  @variable(nlp, lvar[i] <= x[i = 1:n] <= uvar[i], start = x0[i])
+
+  @NLobjective(
+    nlp,
+    Min,
+    sum((sum((1*x[TETS[e+E]+N*i] - x[TETS[e]+N*i])^2 + (2*x[TETS[e+2*E]+N*i] - x[TETS[e+E]+N*i] - x[TETS[e]+N*i])^2 / 3 + (3*x[TETS[e+3*E]+N*i] - x[TETS[e+2*E]+N*i] - x[TETS[e+E]+N*i] - x[TETS[e]+N*i])^2 / 6 for i=0:2))/(3*(sum((x[TETS[e+E]+N*i] - x[TETS[e]+N*i])*((x[TETS[e+2*E]+N*mod(i+1,3)]-x[TETS[e]+N*mod(i+1,3)])*(x[TETS[e+3*E]+N*mod(i-1,3)]-x[TETS[e]+N*mod(i-1,3)])- (x[TETS[e+2*E]+N*mod(i-1,3)]-x[TETS[e]+N*mod(i-1,3)])*(x[TETS[e+3*E]+N*mod(i+1,3)]-x[TETS[e]+N*mod(i+1,3)])) * sqrt(2) for i=0:2))^(2/3)) for e=1:E)
+  )
+
+  for e = 1:E
+    @NLconstraint(
+      nlp,
+      sum((x[TETS[e+E]+N*i] - x[TETS[e]+N*i])*((x[TETS[e+2*E]+N*mod(i+1,3)]-x[TETS[e]+N*mod(i+1,3)])*(x[TETS[e+3*E]+N*mod(i-1,3)]-x[TETS[e]+N*mod(i-1,3)])- (x[TETS[e+2*E]+N*mod(i-1,3)]-x[TETS[e]+N*mod(i-1,3)])*(x[TETS[e+3*E]+N*mod(i+1,3)]-x[TETS[e]+N*mod(i+1,3)])) * sqrt(2) for i=0:2) >= τ
+    )
+  end
+
+  return nlp
+end
+
+include("../../data/tetra_duct12.jl")
+export tetra_duct12
+tetra_duct12(;kwargs...) = tetra(xe_duct12, TETS_duct12, Const_duct12; kwargs...)
+
+include("../../data/tetra_duct15.jl")
+export tetra_duct15
+tetra_duct15(;kwargs...) = tetra(xe_duct15, TETS_duct15, Const_duct15; kwargs...)
+
+include("../../data/tetra_duct20.jl")
+export tetra_duct20
+tetra_duct20(;kwargs...) = tetra(xe_duct20, TETS_duct20, Const_duct20; kwargs...)
+
+include("../../data/tetra_hook.jl")
+export tetra_hook
+tetra_hook(;kwargs...) = tetra(xe_hook, TETS_hook, Const_hook; kwargs...)
+
+include("../../data/tetra_foam5.jl")
+export tetra_foam5
+tetra_foam5(;kwargs...) = tetra(xe_foam5, TETS_foam5, Const_foam5; kwargs...)
+
+include("../../data/tetra_gear.jl")
+export tetra_gear
+tetra_gear(;kwargs...) = tetra(xe_gear, TETS_gear, Const_gear; kwargs...)