deploy: df1de51

_sources/notebooks/01/production-planning-advanced.ipynb

@@ -38,12 +38,7 @@
    "source": [
     "## Preamble: Install Pyomo and a solver\n",
     "\n",
-    "This cell selects and verifies a global SOLVER for the notebook.\n",
-    "\n",
-    "If run on Google Colab, the cell installs Pyomo and HiGHS, then sets SOLVER to \n",
-    "use the Highs solver via the appsi module. If run elsewhere, it assumes Pyomo and CBC\n",
-    "have been previously installed and sets SOLVER to use the CBC solver via the Pyomo \n",
-    "SolverFactory. It then verifies that SOLVER is available."
+    "The following cell checks if the notebook is run on Google Colab. If so, it does a quiet installation of Pyomo and the HiGHS solver. The solver is then selected, a test performed to verify that the solver is available, and the solver interface is stored in a global object `SOLVER` for later use."
    ]
   },
   {
@@ -59,19 +54,17 @@
    "outputs": [],
    "source": [
     "import sys\n",
-    "\n",
+    " \n",
     "if 'google.colab' in sys.modules:\n",
-    "    !pip install pyomo >/dev/null 2>/dev/null\n",
-    "    !pip install highspy >/dev/null 2>/dev/null\n",
-    "\n",
-    "    from pyomo.environ import SolverFactory\n",
-    "    SOLVER = SolverFactory('appsi_highs')\n",
-    "    \n",
-    "else:\n",
-    "    from pyomo.environ import SolverFactory\n",
-    "    SOLVER = SolverFactory('cbc')\n",
-    "\n",
-    "assert SOLVER.available(), f\"Solver {SOLVER} is not available.\""
+    "    %pip install pyomo >/dev/null 2>/dev/null\n",
+    "    %pip install highspy >/dev/null 2>/dev/null\n",
+    " \n",
+    "solver = 'appsi_highs'\n",
+    " \n",
+    "import pyomo.environ as pyo\n",
+    "SOLVER = pyo.SolverFactory(solver)\n",
+    " \n",
+    "assert SOLVER.available(), f\"Solver {solver} is not available.\""
    ]
   },
   {
@@ -332,8 +325,6 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "import pyomo.environ as pyo\n",
-    "\n",
     "model = pyo.ConcreteModel()"
    ]
   },
@@ -552,6 +543,8 @@
       "        labor B :  -Inf : 2*y[U] + y[V] - x[labor B] :   0.0 :   True\n",
       "\n",
       "12 Declarations: PRODUCTS RESOURCES demand available cp cr a_index a x y profit materials_used\n",
+      "Running HiGHS 1.5.3 [date: 2023-05-16, git hash: 594fa5a9d]\n",
+      "Copyright (c) 2023 HiGHS under MIT licence terms\n",
       "Profit = 2600.0\n",
       "\n",
       "Production Report\n",
@@ -601,6 +594,8 @@
      "name": "stdout",
      "output_type": "stream",
      "text": [
+      "Running HiGHS 1.5.3 [date: 2023-05-16, git hash: 594fa5a9d]\n",
+      "Copyright (c) 2023 HiGHS under MIT licence terms\n",
       "Profit = 2600.0\n",
       "\n",
       "Production Report\n",
@@ -615,9 +610,6 @@
     }
    ],
    "source": [
-    "import pyomo.environ as pyo\n",
-    "\n",
-    "\n",
     "class ProductionModel(pyo.ConcreteModel):\n",
     "    \"\"\"\n",
     "    A class representing a production model using Pyomo.\n",
@@ -736,7 +728,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.11.2"
+   "version": "3.10.10"
   },
   "latex_envs": {
    "LaTeX_envs_menu_present": true,