Added a missing requirement that the max dictionary size must be greater than 1.

--HG--
extra : convert_revision : svn%3Afdd8eb12-d10e-0410-9acb-85c331704f74/trunk%403681

dlib/svm/linearly_independent_subset_finder.h

@@ -75,10 +75,11 @@ namespace dlib
             min_tolerance(min_tolerance_)
         {
             // make sure requires clause is not broken
-            DLIB_ASSERT(min_tolerance_ > 0,
+            DLIB_ASSERT(min_tolerance_ > 0 && max_dictionary_size_ > 1,
                 "\tlinearly_independent_subset_finder()"
                 << "\n\tinvalid argument to constructor"
                 << "\n\tmin_tolerance_: " << min_tolerance_
+                << "\n\tmax_dictionary_size_: " << max_dictionary_size_
                 << "\n\tthis:           " << this
                 );
             clear_dictionary();

dlib/svm/linearly_independent_subset_finder_abstract.h

@@ -60,12 +60,13 @@ namespace dlib
 
         linearly_independent_subset_finder (
             const kernel_type& kernel_, 
-            unsigned long max_dictionary_size,
+            unsigned long max_dictionary_size_,
             scalar_type min_tolerance = 0.001
         );
         /*!
             requires
                 - min_tolerance > 0
+                - max_dictionary_size > 1
             ensures
                 - #minimum_tolerance() == min_tolerance
                 - this object is properly initialized