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 # FEMBEM
-
 The **fembem** library provides tools for finite element method and boundary integral equation, using **castor** library. It's a C++ header only library, divided in two .hpp files :
 - __fem.hpp__ for finite elements tools,
-- __bem.hpp__ for integral formulations using boundary elements. 
+- __bem.hpp__ for integral formulations using boundary elements.  
 
 Some executable demos are given to detaill fonctionalities in /demo directory. 
 
-**NOTE :** The **castor** library should be fully installed with graphics tools (VTK) and linear algebra (openblas). For more informations, you can refer to installation procedure of the **castor** library. 
+### Important note :
+- The **castor** library should be fully installed with graphics tools (VTK) and linear algebra (openblas). For more informations, you can refer to installation procedure of the **castor** library. 
+- Compile in relase mode (-O3 or -Os) to improve speed performance. 
 
 ### Authors :
 - Matthieu Aussal (matthieu.aussal@polytechnique.edu)