From 762e68825e8dea8f402dc64bfe8f0213a9bc4088 Mon Sep 17 00:00:00 2001
From: Ni Wang <125902905+gnawin@users.noreply.github.com>
Date: Thu, 18 Apr 2024 12:14:08 +0200
Subject: [PATCH] Modify investment limit to integer when necessary (#582)

---
 src/constraints/investment.jl | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/src/constraints/investment.jl b/src/constraints/investment.jl
index 7b27b9c4..f4ad6f85 100644
--- a/src/constraints/investment.jl
+++ b/src/constraints/investment.jl
@@ -11,20 +11,23 @@ function add_investment_constraints!(graph, Ai, Fi, assets_investment, flows_inv
     # - Maximum (i.e., potential) investment limit for assets
     for a in Ai
         if graph[a].capacity > 0 && !ismissing(graph[a].investment_limit)
-            JuMP.set_upper_bound(
-                assets_investment[a],
-                graph[a].investment_limit / graph[a].capacity,
-            )
+            bound_value = _find_upper_bound(graph, a)
+            JuMP.set_upper_bound(assets_investment[a], bound_value)
         end
     end
 
     # - Maximum (i.e., potential) investment limit for flows
     for (u, v) in Fi
         if graph[u, v].capacity > 0 && !ismissing(graph[u, v].investment_limit)
-            JuMP.set_upper_bound(
-                flows_investment[(u, v)],
-                graph[u, v].investment_limit / graph[u, v].capacity,
-            )
+            bound_value = _find_upper_bound(graph, u, v)
+            JuMP.set_upper_bound(flows_investment[(u, v)], bound_value)
         end
     end
 end
+
+function _find_upper_bound(graph, investments...)
+    bound_value = graph[investments...].investment_limit / graph[investments...].capacity
+    if graph[investments...].investment_integer
+        bound_value = floor(bound_value)
+    end
+end