Made the asserts that checks if the inputs to the optimization functions are

column vectors always enabled since violating this is a common user error.

dlib/optimization/optimization.h

@@ -184,7 +184,7 @@ namespace dlib
         // The starting point (i.e. x) must be a column vector.  
         COMPILE_TIME_ASSERT(T::NC <= 1);
 
-        DLIB_ASSERT (
+        DLIB_CASSERT (
             is_col_vector(x),
             "\tdouble find_min()"
             << "\n\tYou have to supply column vectors to this function"
@@ -244,7 +244,7 @@ namespace dlib
         // The starting point (i.e. x) must be a column vector.  
         COMPILE_TIME_ASSERT(T::NC <= 1);
 
-        DLIB_ASSERT (
+        DLIB_CASSERT (
             is_col_vector(x),
             "\tdouble find_max()"
             << "\n\tYou have to supply column vectors to this function"
@@ -311,7 +311,7 @@ namespace dlib
         // The starting point (i.e. x) must be a column vector.  
         COMPILE_TIME_ASSERT(T::NC <= 1);
 
-        DLIB_ASSERT (
+        DLIB_CASSERT (
             is_col_vector(x) && derivative_eps > 0,
             "\tdouble find_min_using_approximate_derivatives()"
             << "\n\tYou have to supply column vectors to this function"
@@ -374,7 +374,7 @@ namespace dlib
         // The starting point (i.e. x) must be a column vector.  
         COMPILE_TIME_ASSERT(T::NC <= 1);
 
-        DLIB_ASSERT (
+        DLIB_CASSERT (
             is_col_vector(x) && derivative_eps > 0,
             "\tdouble find_max_using_approximate_derivatives()"
             << "\n\tYou have to supply column vectors to this function"
@@ -478,7 +478,7 @@ namespace dlib
         // The starting point (i.e. x) must be a column vector.  
         COMPILE_TIME_ASSERT(T::NC <= 1);
 
-        DLIB_ASSERT (
+        DLIB_CASSERT (
             is_col_vector(x) && is_col_vector(x_lower) && is_col_vector(x_upper) &&
             x.size() == x_lower.size() && x.size() == x_upper.size(),
             "\tdouble find_min_box_constrained()"
@@ -602,7 +602,7 @@ namespace dlib
         // The starting point (i.e. x) must be a column vector.  
         COMPILE_TIME_ASSERT(T::NC <= 1);
 
-        DLIB_ASSERT (
+        DLIB_CASSERT (
             is_col_vector(x) && is_col_vector(x_lower) && is_col_vector(x_upper) &&
             x.size() == x_lower.size() && x.size() == x_upper.size(),
             "\tdouble find_max_box_constrained()"