:term:`MAX_NUM_VECS <MAX_NUM_VECS (DETCI)>` """"""""""""""""""""""""""""""""""""""""""" Maximum number of Davidson subspace vectors which can be held on disk for the CI coefficient and sigma vectors. (There is one H(diag) vector and the number of D vectors is equal to the number of roots). When the number of vectors on disk reaches the value of MAX_NUM_VECS, the Davidson subspace will be collapsed to :term:`COLLAPSE_SIZE <COLLAPSE_SIZE (DETCI)>` vectors for each root. This is very helpful for saving disk space. Defaults to :term:`MAXITER <MAXITER (DETCI)>` * :term:`NUM_ROOTS <NUM_ROOTS (DETCI)>` + :term:`NUM_INIT_VECS <NUM_INIT_VECS (DETCI)>` * **Type**: integer * **Default**: 0