Apply suggestions from code review

Co-authored-by: Andrew Winters <andrew.ross.winters@liu.se>

Author: vincmarks

Project.toml

@@ -11,22 +11,22 @@ StaticArrays = "90137ffa-7385-5640-81b9-e52037218182"
 
 [weakdeps]
 HiGHS = "87dc4568-4c63-4d18-b0c0-bb2238e4078b"
-MathOptInterface = "b8f27783-ece8-5eb3-8dc8-9495eed66fee"
 KernelInterpolation = "95686e15-3c94-4443-8f08-76d06d509f7b"
 Makie = "ee78f7c6-11fb-53f2-987a-cfe4a2b5a57a"
+MathOptInterface = "b8f27783-ece8-5eb3-8dc8-9495eed66fee"
 
 [extensions]
-MathOptInterfaceHiGHSExt = ["HiGHS", "MathOptInterface"]
 KernelInterpolationExt = "KernelInterpolation"
 MakieExt = "Makie"
+MathOptInterfaceHiGHSExt = ["HiGHS", "MathOptInterface"]
 
 [compat]
 Downloads = "1.6"
 HiGHS = "1.0"
-MathOptInterface = "1.0"
 KernelInterpolation = "0.3.5"
 LinearAlgebra = "1"
 Makie = "0.21, 0.22, 0.24"
+MathOptInterface = "1.0"
 SparseArrays = "1"
 StaticArrays = "1.9"
 julia = "1.10"

docs/Project.toml

@@ -3,8 +3,8 @@ CairoMakie = "13f3f980-e62b-5c42-98c6-ff1f3baf88f0"
 Changelog = "5217a498-cd5d-4ec6-b8c2-9b85a09b6e3e"
 Documenter = "e30172f5-a6a5-5a46-863b-614d45cd2de4"
 HiGHS = "87dc4568-4c63-4d18-b0c0-bb2238e4078b"
-MathOptInterface = "b8f27783-ece8-5eb3-8dc8-9495eed66fee"
 KernelInterpolation = "95686e15-3c94-4443-8f08-76d06d509f7b"
+MathOptInterface = "b8f27783-ece8-5eb3-8dc8-9495eed66fee"
 OrdinaryDiffEqLowStorageRK = "b0944070-b475-4768-8dec-fb6eb410534d"
 Trixi = "a7f1ee26-1774-49b1-8366-f1abc58fbfcb"
 TrixiBottomTopography = "86af9953-43df-404b-8eaa-d20d82623a82"
@@ -18,8 +18,8 @@ CairoMakie = "0.13, 0.15"
 Changelog = "1.1"
 Documenter = "1.3"
 HiGHS = "1.0"
-MathOptInterface = "1.0"
 KernelInterpolation = "0.3.5"
+MathOptInterface = "1.0"
 OrdinaryDiffEqLowStorageRK = "1.3"
 Trixi = "0.12, 0.13, 0.14, 0.15, 0.16"
 TrixiShallowWater = "0.2"

ext/MathOptInterfaceHiGHSExt.jl

@@ -78,10 +78,13 @@ function LaverySpline1DModel(len::Int, delta_y::Vector{T}, lambda::T,
     MOI.set(model,
             MOI.ObjectiveFunction{MOI.ScalarAffineFunction{T}}(),
             MOI.ScalarAffineFunction{T}(obj_terms, zero(T)))
+    # Indicate that the objective function should be minimized
     MOI.set(model, MOI.ObjectiveSense(), MOI.MIN_SENSE)
 
     # constraints
-    # abs_E[i,k] constraints
+    # Build constraints from abs(aa[k] * b[i] + bb[k] * b[i + 1] - cc[k] * delta_y[i])
+    # which are nonlinear. Convert into linear constraints by considering each side
+    # of the inequality separately.
     buf3 = Vector{MOI.ScalarAffineTerm{T}}(undef, 3)
     for i in 1:n_sum, k in 1:integral_steps
         s = vars[abs_E_idx(i, k)]
@@ -104,7 +107,7 @@ function LaverySpline1DModel(len::Int, delta_y::Vector{T}, lambda::T,
                            MOI.GreaterThan(cc[k] * delta_y[i]))
     end
 
-    # abs_b[i] constraints
+    # Then come the remaining constraints on the sign of `abs_b[i]`
     buf2 = Vector{MOI.ScalarAffineTerm{T}}(undef, 2)
     for i in 1:n_b
         s = vars[abs_b_idx(i)]
@@ -356,11 +359,8 @@ function LaverySpline2D(x::Vector{T}, y::Vector{T}, z::Matrix{T};
     obj_terms = Vector{MOI.ScalarAffineTerm{T}}(undef, n_vars)
 
     for k in 1:n_vars
-        c = if k <= 2 * n * m
-            lambda            # bx or by block
-        else
-            one(T)            # dxbx, dyby, dyxbx, dxyby blocks
-        end
+        # Assign `lambda` to bx or by block; `one(T)` to dxbx, dyby, dyxbx, dxyby blocks
+        c = k <= 2 * n * m ? lambda : one(T)
         obj_terms[k] = MOI.ScalarAffineTerm{T}(c, vars[k])
     end