NOOPAC
Do not run an operating point (OP) analysis prior to an AC analysis.
This option requires that the circuit is linear, i.e. consists
only of R, L, and C devices, independent V, I sources and linear
dependent E, G, H, and F sources (without poly statement,
non-behavioral). If a non-linear device is detected, the OP analysis
is executed automatically. This option is of interest e.g. in
nested LC circuits where no series resistance for L devices is
present. During the OP analysis an ill-formed matrix may be
encountered, causing the simulator to abort with an error message.