  We present a computer program to calculate the quantised rotational and
hyperfine energy levels of $^{1}\Sigma $ diatomic molecules in the presence of
dc electric, dc magnetic, and off-resonant optical fields. Our program is
applicable to the bialkali molecules used in ongoing state-of-the-art
experiments with ultracold molecular gases. We include functions for the
calculation of space-fixed electric dipole moments, magnetic moments and
transition dipole moments.
