hgu95av2MAPCOUNTS        package:hgu95av2.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 _h_g_u_9_5_a_v_2._d_b

_D_e_s_c_r_i_p_t_i_o_n:

     hgu95av2MAPCOUNTS provides the "map count" (i.e. the count of
     mapped keys) for each map in package hgu95av2.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:

       hgu95av2MAPCOUNTS
       mapnames <- names(hgu95av2MAPCOUNTS)
       hgu95av2MAPCOUNTS[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 hgu95av2.db
       checkMAPCOUNTS("hgu95av2.db")