add nbElements function to all attribute handlers

include/Topology/generic/attributeHandler.h

@@ -135,6 +135,11 @@ public:
 	 */
 	const std::string& name() const ;
 
+	/**
+	 * give the number of elements of the attribute container
+	 */
+	unsigned int nbElements() const;
+
 	/**
 	 * [] operator with dart parameter
 	 */

include/Topology/generic/attributeHandler.hpp

@@ -54,6 +54,7 @@ AttributeHandler<T, ORBIT>::AttributeHandler() :
 	AttributeHandlerGen(NULL, false), m_attrib(NULL)
 {}
 
+
 template <typename T, unsigned int ORBIT>
 AttributeHandler<T, ORBIT>::AttributeHandler(GenericMap* m, AttributeMultiVector<T>* amv) :
 	AttributeHandlerGen(m, false), m_attrib(amv)
@@ -120,6 +121,13 @@ inline const std::string& AttributeHandler<T, ORBIT>::name() const
 	return m_attrib->getName() ;
 }
 
+
+template <typename T, unsigned int ORBIT>
+inline unsigned int AttributeHandler<T, ORBIT>::nbElements() const
+{
+	return m_map->getAttributeContainer<ORBIT>().size() ;
+}
+
 template <typename T, unsigned int ORBIT>
 inline T& AttributeHandler<T, ORBIT>::operator[](Dart d)
 {