Be careful and check your facts @emailsergio UK, some places in Europe, Latin America, Asia and Australasia use the "." as a decimal mark.
Also most technical notation uses the "." as the mark and as we are referring to computer language here it's almost de-facto that "." is used because the "," separates variables.
Also myself and Mark are from the UK not the US
I perfectly except that "5,4" means "5 point 4" (how we say it in my country) but when it comes to computer language it should be learnt that one needs to learn how to use the "." point as the decimal mark.
Finally, did you check out the fact that the person who liked Mark's reply was the very same person he was aiming the reply at. Clearly he didn't think it was rude.