Mu15v1MAPCOUNTS          package:Mu15v1.db          R Documentation

_N_u_m_b_e_r _o_f _m_a_p_p_e_d _k_e_y_s _f_o_r _t_h_e _m_a_p_s _i_n _p_a_c_k_a_g_e _M_u_1_5_v_1._d_b

_D_e_s_c_r_i_p_t_i_o_n:

     Mu15v1MAPCOUNTS provides the "map count" (i.e. the count of mapped
     keys) for each map in package Mu15v1.db.

_D_e_t_a_i_l_s:

     This "map count" information is precalculated and stored in the
     package annotation DB. This allows some quality control and is
     used by the 'checkMAPCOUNTS' function defined in AnnotationDbi to
     compare and validate different methods (like 'count.mappedkeys(x)'
     or 'sum(!is.na(as.list(x)))') for getting the "map count" of a
     given map.

_S_e_e _A_l_s_o:

     'mappedkeys', 'count.mappedkeys', 'checkMAPCOUNTS'

_E_x_a_m_p_l_e_s:

       Mu15v1MAPCOUNTS
       mapnames <- names(Mu15v1MAPCOUNTS)
       Mu15v1MAPCOUNTS[mapnames[1]]
       x <- get(mapnames[1])
       sum(!is.na(as.list(x)))
       count.mappedkeys(x)   # much faster!

       ## Check the "map count" of all the maps in package Mu15v1.db
       checkMAPCOUNTS("Mu15v1.db")

