McLachlan dissipation error

A kind person tells me:

I wanted to mention what appears to be a mistake in your dissipation calculation. If you refer to Kreiss-Oliger, or equivalently to Dissipation/src/apply_dissipation.F77, you find that there is a sign flip at certain orders. For example, 3rd order dissipation to be used with 2nd order differencing, and 7th order dissipation to be used with 6th order differencing, both need a negative coefficient. But you don't appear to have such a minus sign (unless I missed it), and your parameter epsdiss is constrained to be positive. It looks to me like PDdissipationNth needs to be multiplied by something like (-1)^(fdOrder/2).

Keyword: backport

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