In experiment examples, cml contains a parameter theta in <Model> element. For example, in Newport.cml:
<!-- Settings for Model -->
<model type = "BSNQ">
<parameters epsilon = 0.0001 Theta = 2.0 correctionStepsNum = 0 timestep = 0.014876></parameters>
<friction type = "Mannings" coef = 0.02></friction>
So far I feel I didn't read any clarification for it. Could you please tell me what's the meaning of it?
BTW, do you think it's possible or convenient to add a figure to clarify the relationship between x,y-direction/ coordinate and east/west/south/north directions in the manual of coming edition?
Thanks for your post. Theta in the <model> is the coefficient of the minmod limiter that we use. It can change between 1 (most dissipative) to 2 (least dissipative). Smaller theta results in a more stable simulation, but in expense of more numerical dissipation. See our paper in CPC or this article on Wikipedia: https://en.wikipedia.org/wiki/Flux_limiter#Generalised_minmod_limiter
Regarding the User Manual, you are right. We need to publish an updated version as many new features are not covered. The west and east boundaries are perpendicular to the x axis, with the west standing on the lowest x value. The north and south boundaries are perpendicular to the y axis, with the south standing on the lowest y value.