On Sunday 14 October 2007, Karel Kulhavy wrote:
What does the Operating Point Analysis (op) take for the DC
value if a time-dependent function (for example pwl) is
specified in current or voltage source? Is it zero? Or the
value of the function in time point zero?
It takes the value at time point zero.
If you want it to be zero, say "DC 0".
It is supposed to be Spice compatible.
You didn't ask, but the AC analysis takes the operating point
from the most recent DC, OP, or tran point. This differs from
Spice, which always takes "op".