Method prop_up

examples/machine_learning/rbm.cpp:61–64

        , v_bias(constant(0, 1, v_size)) {}

    array prop_up(const array &v) {
        array h_bias_tile = tile(h_bias, v.dims(0));
        return sigmoid(h_bias_tile + matmulNT(v, weights));
    }

    array prop_down(const array &h) {
        array v_bias_tile = tile(v_bias, h.dims(0));