Add facility_location as a valid test

docs/quadratic_expressions.md

@@ -4,10 +4,24 @@ Quadratic expressions work as you'd expect. Simply multiply two linear expressio
 
 ## Example
 
-## TODO
+### Maximize area of box
+Here's a short example that shows that a square maximizes the area of any box with a fixed perimeter.
 
 ```python3
+import pyoframe as pf
+model = pf.Model("max")
+model.w = pf.Variable(lb=0)
+model.h = pf.Variable(lb=0)
+model.limit_perimter = 2 * (model.w + model.h) <= 20
+model.objective = model.w * model.h
+model.solve()
+print(f"It's a square: {model.w.solution==model.h.solution}")
+
+# Outputs: It's a square: True
 ```
+### Facility Location Problem
+
+See [examples/facility_location](../tests/examples/facility_location/).
 
 ## Note for Pyoframe developers: Internal Representation of Quadratics
 

src/pyoframe/core.py

@@ -107,7 +107,7 @@ def __pow__(self, power: int):
         >>> from pyoframe import Variable
         >>> Variable() ** 2
         <Expression size=1 dimensions={} terms=1 degree=2>
-        x1*x1
+        x1 * x1
         """
         if power == 2:
             return self * self
@@ -726,10 +726,10 @@ def _add_const(self, const: int | float) -> Expression:
         x1 +5
         >>> Variable() ** 2 + 5
         <Expression size=1 dimensions={} terms=2 degree=2>
-        x2*x2 +5
+        x2 * x2 +5
         >>> Variable() ** 2 + Variable() + 5
         <Expression size=1 dimensions={} terms=3 degree=2>
-        x3*x3 + x4 +5
+        x3 * x3 + x4 +5
         """
         dim = self.dimensions
         data = self.data

tests/examples/facility_location/model.py

@@ -4,7 +4,7 @@
 from pathlib import Path
 
 
-def main(G, F, **kwargs):
+def main(G=4, F=3, **kwargs):
     model = pf.Model("min")
 
     g_range = range(G)
@@ -53,7 +53,7 @@ def main(G, F, **kwargs):
     return model
 
 
-def draw_results(model, G, T):
+def draw_results(model, G, F):
     import tkinter
 
     root = tkinter.Tk()
@@ -100,6 +100,6 @@ def draw_results(model, G, T):
         F,
         directory=working_dir / "results",
         use_var_names=True,
-        solution_file=working_dir / "results" / "solution.sol",
+        solution_file=working_dir / "results" / "pyoframe-problem.sol",
     )
     draw_results(model, G, F)

tests/test_examples.py

@@ -27,6 +27,11 @@ class Example:
         many_valid_solutions=True,
         has_gurobi_version=False,
     ),
+    Example(
+        "facility_location",
+        has_gurobi_version=False,
+        many_valid_solutions=True,
+    ),
 ]
 
 
@@ -49,15 +54,19 @@ def test_examples(example: Example):
     symbolic_solution_file = symbolic_output_dir / "pyoframe-problem.sol"
     dense_solution_file = dense_output_dir / "pyoframe-problem.sol"
 
-    symbolic_model = main_module.main(
-        input_dir,
+    symbolic_kwargs = dict(
         directory=symbolic_output_dir,
         solution_file=symbolic_solution_file,
         use_var_names=True,
     )
-    dense_model = main_module.main(
-        input_dir, directory=dense_output_dir, solution_file=dense_solution_file
-    )
+    dense_kwargs = dict(directory=dense_output_dir, solution_file=dense_solution_file)
+
+    if input_dir.exists():
+        symbolic_kwargs["input_dir"] = input_dir
+        dense_kwargs["input_dir"] = input_dir
+
+    symbolic_model = main_module.main(**symbolic_kwargs)
+    dense_model = main_module.main(**dense_kwargs)
 
     if example.check_params is not None:
         for param, value in example.check_params.items():