how to discard all punctuation from a text file

Hello,I need a matlab code to discard all punctuation and signs from a text file and just keep charactere and numbers.thanks

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What did not work in my Answer to your Question in: How to discard all punctuation from a text file?

[Walter Roberson]

Duplicated by http://www.mathworks.com/matlabcentral/answers/264231-how-to-discard-all-punctuation-from-a-text-file