[outA, ixA, outB, ixB] = semijoin (A, B) ¶Natural semijoin.
Computes the natural semijoin of tables A and B. The semi-join of tables A and B is the set of all rows in A which have matching rows in B, based on comparing the values of variables with the same names.
This method also computes the semijoin of B and A, for convenience.
Returns: outA - all the rows in A with matching row(s) in B ixA - the row indexes into A which produced outA outB - all the rows in B with matching row(s) in A ixB - the row indexes into B which produced outB