17522b968c8a1d2b29d0034fc57cec59ed9972de,pymanopt/tools/autodiff/_tensorflow.py,TensorflowBackend,compute_hessian,#TensorflowBackend#,76

Before Change

    @assert_backend_available
    def compute_hessian(self, objective, argument):
        // TODO
        raise NotImplementedError("Tensorflow backend does not yet "
                                  "implement compute_hessian.")

After Change

    @assert_backend_available
    def compute_hessian(self, objective, argument):
        if not isinstance(argument, list):
            argA = tf.Variable(tf.zeros(tf.shape(argument)))
            tfhess = _hessian_vector_product(objective, [argument], [argA])

            def hess(x, a):
                feed_dict = {argument: x, argA: a}
                return self._session.run(tfhess[0], feed_dict)

        else:
            argA = [tf.Variable(tf.zeros(tf.shape(arg)))
                    for arg in argument]
            tfhess = _hessian_vector_product(objective, argument, argA)

            def hess(x, a):
                feed_dict = {i: d for i, d in zip(argument+argA, x+a)}
                return self._session.run(tfhess, feed_dict)

        return hess

Instances