The trend for D and F block elements are same as the rest of the elements, in the fact that atomic or ionic radii increases down the group and decreases across a period. However, in case of D and F block elements, you do not see this happeneing significantly because of the shielding effect of the D and F block electrons. This means thats the D and F orbitals of the penultimate shell starts filling up after the last shell of the atom is already filled. Thus, it does not lead to increase in the size of the atom or ion.