Support for solution summaries

Author: petercoles

src/Solution.php

@@ -47,6 +47,11 @@ public function chromosomes()
         return $this->chromosomes;
     }
 
+    public function summary()
+    {
+        return (object) ['fitness' => $this->fitness, 'chromosomes' => implode(':', $this->chromosomes)];
+    }
+
     protected function randomChar($chromosome)
     {
         return $chromosome[1][mt_rand(0, strlen($chromosome[1]) - 1)];

tests/SolutionSummaryTest.php

@@ -0,0 +1,43 @@
+<?php
+
+namespace PeterColes\GAO\Tests;
+
+use PHPUnit\Framework\TestCase;
+use PeterColes\GAO\Tests\Solutions\Floats;
+use PeterColes\GAO\Tests\Solutions\Integers;
+
+class SolutionSummaryTest extends TestCase
+{
+    public function setUp()
+    {
+        parent::setUp();
+
+        mt_srand(0); // seed random number generator for consistent test results
+    }
+
+    /** @test */
+    public function can_summarise_solution()
+    {
+        $solution = new Integers();
+        $solution->initialise();
+        $solution->evaluate([[10, 5, 1]]);
+
+        $summary = $solution->summary();
+
+        $this->assertEquals(446, $summary->fitness);
+        $this->assertEquals('64:-39:1', $summary->chromosomes);
+    }
+
+    /** @test */
+    public function can_tailor_solution_summaries()
+    {
+        $solution = new Floats();
+        $solution->initialise();
+        $solution->evaluate();
+
+        $summary = $solution->summary();
+
+        $this->assertEquals(15.570, $summary->fitness);
+        $this->assertEquals([54.88, -40.72, 0.72, 0.69], $summary->chromosomes);
+    }
+}

tests/Solutions/Floats.php

@@ -16,8 +16,18 @@ public function genome()
         ];
     }
 
-    public function evaluate($data)
+    public function evaluate($data = null)
     {
-        //
+        $this->fitness = collect($this->chromosomes)->sum();
+    }
+
+    public function summary()
+    {
+        return (object) [
+            'fitness' => number_format($this->fitness, 3),
+            'chromosomes' => collect($this->chromosomes)->map(function ($chromosome) {
+                return number_format($chromosome, 2);
+            })->toArray(),
+        ];
     }
 }