Arbitrary Input State Capabilities

[zphy]

Are there functionalities in TFQ that allow one to specify an arbitrary input state in the 2^N Hilbert space? I understand that one could in principle make a circuit to prepare such a state, but in the case where, for example, the input state comes from solving the ground state of a many-body Hamiltonian, this might be very expensive to do, and it would be useful to be able to have an interface directly specifying this as a state vector/density matrix.