  We develop an algorithm to compute Fourier expansions of vector valued
modular for Weil representations. As an application, we compute explicit linear
equivalences of special divisors on modular varieties of orthogonal type. We
define three families of Hecke operators for Jacobi forms, and analyze the
induced action on vector valued modular forms. The newspaces attached to one of
these families are used to give a more memory efficient version of our
algorithm.
