- Made the vector class inherit from matrix

  - Added code to make sure the vector class does the
    appropriate type promotion when vector objects
    with different types are used together.

--HG--
extra : convert_revision : svn%3Afdd8eb12-d10e-0410-9acb-85c331704f74/trunk%402736

dlib/geometry/vector_abstract.h

@@ -14,7 +14,7 @@ namespace dlib
         typename T,
         long NR = 3
         >
-    class vector
+    class vector : public matrix<T,NR,1>
     {
         /*!
             REQUIREMENTS ON T
@@ -129,21 +129,6 @@ namespace dlib
                         - #z() == 0
         !*/
 
-        operator matrix<T> (
-        ) const;
-        /*!
-            ensures
-                - provides automatic conversions from a vector object to a column 
-                  matrix
-                - returns a matrix object m such that:
-                    - m.nr() == NR
-                    - m.nc() == 1
-                    - m(0) == x()
-                    - m(1) == y()
-                    - if (NR == 3) then
-                        - m(2) == z()
-        !*/
-
         ~vector (
         );
         /*!

dlib/test/geometry.cpp

@@ -186,6 +186,22 @@ namespace
             DLIB_CASSERT(vl2.cross(vl3).length() == 12,"");
             DLIB_CASSERT(vl3.cross(vl2).length() == 12,"");
 
+
+            matrix<double> m(3,3);
+            m = 1,2,3,
+                4,5,6,
+                7,8,9;
+
+            vd3.x() = 2;
+            vd3.y() = 3;
+            vd3.z() = 4;
+
+            vd3 = m*vd3;
+
+            DLIB_CASSERT(vd3.x() == 1*2 + 2*3 + 3*4,vd3.x() << " == " << (1*2 + 2*3 + 3*4));
+            DLIB_CASSERT(vd3.y() == 4*2 + 5*3 + 6*4,"");
+            DLIB_CASSERT(vd3.z() == 7*2 + 8*3 + 9*4,"");
+
         }
 
     }