Previous solutions only considered commas and periods, not other punctuation symbols. Assuming anything that's not a word character or whitespace is to be considered punctuation, I would use: 
    s/(\d[,.]\d)|([^\w\s](?!\s))/$1 || "$2 "/ge;

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Abigail

In reply to Re: Regex to add space after punctuation sign by Abigail-II
in thread Regex to add space after punctuation sign by dda

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