R2N: compute opnorm for hessian in sparseCOO format

Author: MaxenceGollier

src/R2N.jl

@@ -304,17 +304,13 @@ function SolverCore.solve!(
   λmax::T = T(1)
   if !solver.store_h 
     solver.subpb.model.B = hess_op(nlp, xk)
-  else
-    hess_coord!(nlp, xk, solver.subpb.model.B.vals)
-  end
-
-  if opnorm_maxiter ≤ 0
     λmax, found_λ = opnorm(solver.subpb.model.B)
+    found_λ || error("operator norm computation failed")
   else
-    λmax = power_method!(solver.subpb.model.B, solver.v0, solver.subpb.model.v, opnorm_maxiter)
+    hess_coord!(nlp, xk, solver.subpb.model.B.vals)
+    λmax = opnorm(solver.subpb.model.B)
   end
-  found_λ || error("operator norm computation failed")
-
+  
   ν₁ = θ / (λmax + σk)
 
   sqrt_ξ1_νInv = one(T)
@@ -461,16 +457,14 @@ function SolverCore.solve!(
       end
       if !solver.store_h 
         solver.subpb.model.B = hess_op(nlp, xk)
-      else
-        hess_coord!(nlp, xk, solver.subpb.model.B.vals)
-      end
-
-      if opnorm_maxiter ≤ 0
         λmax, found_λ = opnorm(solver.subpb.model.B)
+        found_λ || error("operator norm computation failed")
       else
-        λmax = power_method!(solver.subpb.model.B, solver.v0, solver.subpb.model.v, opnorm_maxiter)
+        hess_coord!(nlp, xk, solver.subpb.model.B.vals)
+        λmax = opnorm(solver.subpb.model.B)
       end
-      found_λ || error("operator norm computation failed")
+      
+      ∇fk⁻ .= ∇fk
     end
 
     if η2 ≤ ρk < Inf