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In the LibreOfficeDev Calc functions, parameters marked as "optional" can be left out only when no parameter follows. For example, in a function with four parameters, where the last two parameters are marked as "optional", you can leave out parameter 4 or parameters 3 and 4, but you cannot leave out parameter 3 alone.
大於 127 的代碼會視系統的字元對映而定 (例如 iso-8859-1、iso-8859-2、Windows-1252、Windows-1250)，因此無法移植。
