diff --git a/dlib/svm/kernel_matrix.h b/dlib/svm/kernel_matrix.h
index 028cb9c84..ac398436c 100644
--- a/dlib/svm/kernel_matrix.h
+++ b/dlib/svm/kernel_matrix.h
@@ -7,6 +7,7 @@
 #include "kernel_matrix_abstract.h"
 #include "../matrix.h"
 #include "../algs.h"
+#include "../statistics/random_subset_selector.h"
 
 namespace dlib
 {
@@ -23,6 +24,12 @@ namespace dlib
             return m(i);
         }
 
+        template <typename kernel_type, typename T, typename Rand_type>
+        inline const T& access ( const random_subset_selector<T,Rand_type>& m, long i)
+        {
+            return m[i];
+        }
+
         template <typename kernel_type, typename T, typename alloc>
         inline const T& access ( const std::vector<T,alloc>& m, long i)
         {
@@ -52,6 +59,12 @@ namespace dlib
             return m.size();
         }
 
+        template <typename kernel_type, typename T, typename Rand_type>
+        inline unsigned long size ( const random_subset_selector<T,Rand_type>& m)
+        {
+            return m.size();
+        }
+
         template <typename kernel_type, typename T, typename alloc>
         inline unsigned long size ( const std::vector<T,alloc>& m)
         {
diff --git a/dlib/svm/kernel_matrix_abstract.h b/dlib/svm/kernel_matrix_abstract.h
index 3afef2383..6638bb608 100644
--- a/dlib/svm/kernel_matrix_abstract.h
+++ b/dlib/svm/kernel_matrix_abstract.h
@@ -25,7 +25,8 @@ namespace dlib
         requires
             - kernel == a kernel function object as defined by the file dlib/svm/kernel_abstract.h.
               This kernel must also be capable of operating on the contents of v.
-            - V == dlib::matrix, std::vector, dlib::std_vector_c, or kernel_type::sample_type.
+            - V == dlib::matrix, std::vector, dlib::std_vector_c, dlib::random_subset_selector, or 
+              kernel_type::sample_type.
             - if (V is a dlib::matrix) then
                 - is_vector(v) == true
         ensures
@@ -58,8 +59,10 @@ namespace dlib
         requires
             - kernel == a kernel function object as defined by the file dlib/svm/kernel_abstract.h
               This kernel must also be capable of operating on the contents of v1 and v2.
-            - V1 == dlib::matrix, std::vector, dlib::std_vector_c, or kernel_type::sample_type.
-            - V2 == dlib::matrix, std::vector, dlib::std_vector_c, or kernel_type::sample_type.
+            - V1 == dlib::matrix, std::vector, dlib::std_vector_c, dlib::random_subset_selector, or 
+              kernel_type::sample_type.
+            - V2 == dlib::matrix, std::vector, dlib::std_vector_c, dlib::random_subset_selector, or 
+              kernel_type::sample_type.
             - if (V1 is a dlib::matrix) then
                 - is_vector(v1) == true
             - if (V2 is a dlib::matrix) then