Added a kmeans test

--HG--
rename : dlib/test/hash.cpp => dlib/test/kmeans.cpp

dlib/test/CMakeLists.txt

@@ -53,6 +53,7 @@ set (tests
    is_same_object.cpp
    kcentroid.cpp
    kernel_matrix.cpp
+   kmeans.cpp
    least_squares.cpp
    linear_manifold_regularizer.cpp
    lz77_buffer.cpp

dlib/test/kmeans.cpp

+// Copyright (C) 2011  Davis E. King (davis@dlib.net)
+// License: Boost Software License   See LICENSE.txt for the full license.
+
+#include <sstream>
+#include <string>
+#include <cstdlib>
+#include <ctime>
+#include <dlib/svm.h>
+#include <dlib/matrix.h>
+
+#include "tester.h"
+
+namespace  
+{
+    using namespace test;
+    using namespace dlib;
+    using namespace std;
+
+    logger dlog("test.kmeans");
+
+    dlib::rand rnd;
+
+    template <typename sample_type>
+    void run_test(
+        const std::vector<sample_type>& seed_centers
+    )
+    {
+        print_spinner();
+
+
+        sample_type samp;
+
+        std::vector<sample_type> samples;
+
+
+        for (unsigned long j = 0; j < seed_centers.size(); ++j)
+        {
+            for (int i = 0; i < 250; ++i)
+            {
+                samp = randm(seed_centers[0].size(),1,rnd) - 0.5;
+                samples.push_back(samp + seed_centers[j]);
+            }
+        }
+
+        randomize_samples(samples);
+
+        std::vector<sample_type> centers;
+        pick_initial_centers(seed_centers.size(), centers, samples, linear_kernel<sample_type>());
+
+        DLIB_TEST(centers.size() == seed_centers.size());
+
+        std::vector<int> hits(centers.size(),0);
+        for (unsigned long i = 0; i < samples.size(); ++i)
+        {
+            unsigned long best_idx = 0;
+            double best_dist = 1e100;
+            for (unsigned long j = 0; j < centers.size(); ++j)
+            {
+                if (length(samples[i] - centers[j]) < best_dist)
+                {
+                    best_dist = length(samples[i] - centers[j]);
+                    best_idx = j;
+                }
+            }
+            hits[best_idx]++;
+        }
+
+        for (unsigned long i = 0; i < hits.size(); ++i)
+        {
+            DLIB_TEST(hits[i] == 250);
+        }
+    }
+
+
+    class test_kmeans : public tester
+    {
+    public:
+        test_kmeans (
+        ) :
+            tester ("test_kmeans",
+                    "Runs tests on the find_clusters_using_kmeans() function.")
+        {}
+
+        void perform_test (
+        )
+        {
+            {
+                dlog << LINFO << "test dlib::vector<double,2>";
+                typedef dlib::vector<double,2> sample_type;
+                std::vector<sample_type> seed_centers;
+                seed_centers.push_back(sample_type(10,10));
+                seed_centers.push_back(sample_type(10,-10));
+                seed_centers.push_back(sample_type(-10,10));
+                seed_centers.push_back(sample_type(-10,-10));
+
+                run_test(seed_centers);
+            }
+            {
+                dlog << LINFO << "test dlib::matrix<double,3,1>";
+                typedef dlib::matrix<double,3,1> sample_type;
+                std::vector<sample_type> seed_centers;
+                sample_type samp;
+                samp = 10,10,0; seed_centers.push_back(samp);
+                samp = -10,10,1; seed_centers.push_back(samp);
+                samp = -10,-10,2; seed_centers.push_back(samp);
+
+                run_test(seed_centers);
+            }
+
+
+        }
+    } a;
+
+
+
+}
+
+
+

dlib/test/makefile

@@ -63,6 +63,7 @@ SRC += image.cpp
 SRC += is_same_object.cpp
 SRC += kcentroid.cpp
 SRC += kernel_matrix.cpp
+SRC += kmeans.cpp
 SRC += least_squares.cpp
 SRC += linear_manifold_regularizer.cpp
 SRC += lz77_buffer.cpp