We consider a class of trigonometric solutions of Witten–Dijkgraaf–Verlinde–Verlinde equations determined by collections of vectors with multiplicities. We show that such solutions can be restricted to special subspaces to produce new solutions of the same type. We find new solutions given by restrictions of root systems, as well as examples which are not of this form. Further, we consider a closely related notion of a trigonometric ∨-system, and we show that its subsystems are also trigonometric ∨-systems. Finally, while reviewing the root system case we determine a version of (generalised) Coxeter number for the exterior square of the reflection representation of a Weyl group.

我们考虑一类由多重矢量集合确定的维滕-迪克格拉夫-韦林德-韦林德方程的三角解。我们表明，此类解决方案可以限制在特殊子空间中，以产生相同类型的新解决方案。我们发现了受根系统限制而给出的新解决方案，以及非此形式的示例。此外，我们考虑了三角∨系统的一个密切相关的概念，并且证明了它的子系统也是三角∨系统。最后，在查看根系统情况的同时，我们确定Weyl群反射表示的外部平方的（广义）Coxeter数版本。