Added some regression tests for the svm/kernel methods stuff

--HG--
extra : convert_revision : svn%3Afdd8eb12-d10e-0410-9acb-85c331704f74/trunk%402490

dlib/test/CMakeLists.txt

@@ -60,6 +60,7 @@ set (tests
    static_map.cpp
    static_set.cpp
    string.cpp
+   svm.cpp
    threads.cpp
    timer.cpp
    tokenizer.cpp

dlib/test/checkerboard.h

+#ifndef DLIB_CHECKERBOARD_TeST_H_
+#define DLIB_CHECKERBOARD_TeST_H_
+
+#include <dlib/matrix.h>
+#include <vector>
+#include <dlib/rand.h>
+
+namespace dlib
+{
+
+    void get_checkerboard_problem (
+        std::vector<matrix<double,2,1> >& x,
+        std::vector<double>& y,
+        const long num_samples,
+        const long board_dimension = 8
+    )
+    /*!
+        requires
+            - num_samples > 0
+            - board_dimension > 0
+        ensures
+            - #x.size() == y.size() == num_samples
+            - is_binary_classification_problem(#x,#y) == true
+            - #x will contain points and #y labels that were
+              sampled randomly from a checkers board that has 
+              board_dimension squares on each side. 
+    !*/
+    {
+        static dlib::rand::float_1a rnd;
+
+        x.clear();
+        y.clear();
+
+        matrix<double,2,1> sample;
+        for (long i = 0; i < num_samples; ++i)
+        {
+            sample(0) = rnd.get_random_double();
+            sample(1) = rnd.get_random_double();
+            sample *= board_dimension;
+
+            x.push_back(sample);
+            if (((int)sum(floor(sample)) %2) == 0)
+                y.push_back(+1);
+            else
+                y.push_back(-1);
+            
+        }
+    }
+
+
+}
+
+#endif // DLIB_CHECKERBOARD_TeST_H_
+