We classify blocks of category $\mathcal{O}$ for rational Cherednik algebras
and of cyclotomic Hecke algebras of type G(r,p,n) by using the "residue
equivalence" for multi-partitions.
We give a presentation of cyclotomic q-Schur algebras by generators and
defining relations. As an application, we give an algorithm for computing
decomposition numbers of cyclotomic q-Schur algebras.