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-trbdfErrorMethod method

specifies the which approach is used to estimate the local truncation error and which norm is used. The available methods are dd/pointwise (divided differences for LTE estimate with a pointwise norm to measure the error), dd/global (divided differences for the LTE estimate with a global norm to measure the error), and milne, which uses a Milne's device to estimate the LTE and a pointwise norm to measure the error. The Milne approach uses a second TR step over the second half of the interval (and, hence an expensive third nonlinear solve). Although that approach has had a good deal of success with quasi-equilibrium diffusion models, it seem to be prone to oscillations from the lack of A-stability in the TR-TR step when used with fully kinetic models.

The default is dd/pointwise.



Dan Yergeau
Wed Aug 20 14:01:54 PDT 1997