Fixed some warnings and made the unit tests more robust.

dlib/optimization/optimization_solve_qp_using_smo.h

@@ -465,7 +465,7 @@ namespace dlib
 
         // First we use a coordinate descent method to initialize alpha. 
         double max_df = 0;
-        for (unsigned long iter = 0; iter < alpha.size()*2; ++iter)
+        for (long iter = 0; iter < alpha.size()*2; ++iter)
         {
             max_df = 0;
             long best_r =0;

dlib/test/mpc.cpp

@@ -328,8 +328,8 @@ namespace
                 lower = -4;
                 upper = 3;
 
-                solve_qp_box_using_smo(Q,b,alpha,lower, upper, 0.00000001, 100000);
-                solve_qp_box_constrained(Q,b,alpha2,lower, upper, 0.00000001, 10000);
+                solve_qp_box_using_smo(Q,b,alpha,lower, upper, 0.000000001, 500000);
+                solve_qp_box_constrained(Q,b,alpha2,lower, upper, 0.000000001, 50000);
                 dlog << LINFO << trans(alpha);
                 dlog << LINFO << trans(alpha2);
                 dlog << LINFO << "objective value:  " << 0.5*trans(alpha)*Q*alpha + trans(b)*alpha;