Fixed dlib::abs() so that it works right on complex matrices.

--HG--
extra : convert_revision : svn%3Afdd8eb12-d10e-0410-9acb-85c331704f74/trunk%402846

dlib/matrix/matrix_math_functions.h

@@ -36,7 +36,6 @@ namespace dlib
 
 // ----------------------------------------------------------------------------------------
 
-DLIB_MATRIX_SIMPLE_STD_FUNCTION(abs,7)
 DLIB_MATRIX_SIMPLE_STD_FUNCTION(sqrt,7)
 DLIB_MATRIX_SIMPLE_STD_FUNCTION(log,7)
 DLIB_MATRIX_SIMPLE_STD_FUNCTION(log10,7)
@@ -342,6 +341,46 @@ DLIB_MATRIX_SIMPLE_STD_FUNCTION(atan,7)
         return exp(m.ref());
     }
 
+// ----------------------------------------------------------------------------------------
+
+    struct op_abs
+    {
+        template <typename EXP, typename return_type = typename EXP::type>
+        struct op : has_nondestructive_aliasing, preserves_dimensions<EXP>
+        {
+            const static long cost = EXP::cost+7;
+            typedef typename EXP::type type;
+            template <typename M>
+            static type apply ( const M& m, long r, long c)
+            { 
+                return static_cast<type>(std::abs(m(r,c))); 
+            }
+        };
+
+        template <typename EXP, typename T>
+        struct op<EXP, std::complex<T> > : has_nondestructive_aliasing, preserves_dimensions<EXP>
+        {
+            const static long cost = EXP::cost;
+            typedef T type;
+            template <typename M>
+            static type apply ( const M& m, long r, long c)
+            { 
+                return static_cast<type>(std::abs(m(r,c))); 
+            }
+        };
+    };
+
+    template <
+        typename EXP
+        >
+    const matrix_unary_exp<EXP,op_abs> abs (
+        const matrix_exp<EXP>& m
+    )
+    {
+        typedef matrix_unary_exp<EXP,op_abs> exp;
+        return exp(m.ref());
+    }
+
 // ----------------------------------------------------------------------------------------
 
     struct op_complex_matrix

dlib/matrix/matrix_math_functions_abstract.h

@@ -140,10 +140,14 @@ namespace dlib
     /*!
         ensures
             - returns a matrix R such that:
-                - R::type == the same type that was in m
+                - if (m contains std::complex<T> objects) then
+                    - R::type == T 
+                - else
+                    - R::type == the same type that was in m
                 - R has the same dimensions as m
                 - for all valid r and c:
                   R(r,c) == std::abs(m(r,c)) 
+                  (note that if m is complex then std::abs(val) performs sqrt(std::norm(val))
     !*/
 
 // ----------------------------------------------------------------------------------------

dlib/test/makefile

@@ -54,6 +54,7 @@ SRC += map.cpp
 SRC += matrix.cpp
 SRC += matrix2.cpp
 SRC += matrix3.cpp
+SRC += matrix_la.cpp
 SRC += md5.cpp
 SRC += member_function_pointer.cpp
 SRC += metaprogramming.cpp