Added more sparse vector tools and fixed a bug.

tools/python/src/other.cpp

 #include <boost/python.hpp>
 #include <boost/shared_ptr.hpp>
 #include <dlib/matrix.h>
+#include <dlib/data_io.h>
+#include <dlib/sparse_vector.h>
 
 using namespace dlib;
 using namespace std;
 using namespace boost::python;
 
+typedef std::vector<std::pair<unsigned long,double> > sparse_vect;
+
 tuple get_training_data()
 {
     typedef matrix<double,0,1> sample_type;
@@ -28,8 +32,43 @@ tuple get_training_data()
     return make_tuple(samples, labels);
 }
 
+void _make_sparse_vector (
+    sparse_vect& v
+)
+{
+    make_sparse_vector_inplace(v);
+}
+
+void _make_sparse_vector2 (
+    std::vector<sparse_vect>& v
+)
+{
+    for (unsigned long i = 0; i < v.size(); ++i)
+        make_sparse_vector_inplace(v[i]);
+}
+
+tuple _load_libsvm_formatted_data (
+    const std::string& file_name
+) 
+{ 
+    std::vector<sparse_vect> samples;
+    std::vector<double> labels;
+    load_libsvm_formatted_data(file_name, samples, labels); 
+    return make_tuple(samples, labels);
+}
+
+void _save_libsvm_formatted_data (
+    const std::string& file_name,
+    const std::vector<sparse_vect>& samples,
+    const std::vector<double>& labels
+) { save_libsvm_formatted_data(file_name, samples, labels); }
+
 void bind_other()
 {
     def("get_training_data",get_training_data);
+    def("make_sparse_vector", _make_sparse_vector , "This function modifies its argument so that it is a properly sorted sparse vector.");
+    def("make_sparse_vector", _make_sparse_vector2 , "This function modifies a sparse_vectors object so that all elements it contains are properly sorted sparse vectors.");
+    def("load_libsvm_formatted_data",_load_libsvm_formatted_data);
+    def("save_libsvm_formatted_data",_save_libsvm_formatted_data);
 }
 

tools/python/src/svm_c_trainer.cpp

@@ -177,7 +177,7 @@ void bind_svm_c_trainer()
     {
         typedef svm_c_trainer<sparse_radial_basis_kernel<sparse_vect> > T;
         setup_trainer2<T>("svm_c_trainer_sparse_radial_basis")
-            .add_property("gamma", get_gamma, set_gamma);
+            .add_property("gamma", get_gamma_sparse, set_gamma_sparse);
         def("cross_validate_trainer", _cross_validate_trainer<T>);
         def("cross_validate_trainer_threaded", _cross_validate_trainer_t<T>);
     }