An exemplification of the vertical partition of BI, J(the entries of BI, Jare dotted). (a) The pre-condition requires that all values in B[I,J], [I,J], excluding BI, J, are computed, and B
= βI,(I,J)⊗ β (I,J),J(see Figure 7). (b) B
is partitioned vertically to and , where is computed recursively. (c) The pre-condition for computing is established, by updating to be (in this example L = J1, since I ends before J1 starts). Then, is computed recursively (not shown).