Create the file using a text editor, for example Microsoft Notepad.
Each row in the file defines a material. Use the following syntax: material_name symbol_file_name@n , where
Warning: The order of material names in the definition file is relevant to the conversion. Materials with more specific names need to be listed before the ones with similar, but simpler names, for example, S235JRG1 must be listed before S235JR. Otherwise they both get the same symbol.