$RCWAxnode

The $RCWAxnode command is used to define the position of boundary point in each layer which assigned in $RCWAxdiv. It also needs to goes with the $RCWAxdiv and $RCWAperiod to define number of boundary point and the period of simulation domain. The left boundary point does not need to assign which automatically set as -period/2.

$RCWAxnode

-10000 10000 30000 
-10000 10000 30000 
-10000 -2500 2500 10000 30000 
-10000 10000 30000 
-10000 10000 30000 
...
total layer

The $RCWAxnode setting in GUI interface is here
1. Press Add new layers for RCWA and fill in the fields starting from the 2^nd one, as needed!