In version 4.0a, the property nonlin in the stationary solver could have the values
auto,
on,
off, and
linearized. The default in most cases was
auto, but in some cases, specifically in a frequency-domain study, the default was
linearized. In version 4.1, the possible values are
auto,
on,
off, and
linper, with
auto as default, except in the Frequency Domain, Linearized study step where the default is
linper. The value
linearized can still be set, but this is treated as
auto. If the problem is linear and the linearization point is zero,
auto should give the same solution as
linearized. For nonlinear problems where the linearization point is zero, the solution given by
auto might be slightly different, and probably more accurate, while changing to
off should give exactly the same solution as
linearized. When there is a nonzero linearization point, it is relevant to use the
linper option. This option works like
linearized, except that source terms that contribute to the linearized problem must be enclosed by the
linper operator.