itemsets-class            package:arules            R Documentation

_C_l_a_s_s "_i_t_e_m_s_e_t_s" - _A _S_e_t _o_f _I_t_e_m_s_e_t_s

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

     The 'itemsets' class represents a set of itemsets and the
     associated quality measures.

_O_b_j_e_c_t_s _f_r_o_m _t_h_e _C_l_a_s_s:

     Objects are the result of calling the functions 'apriori' (e.g.,
     with 'target="frequent itemsets"' in the parameter list)  or
     'eclat'. Objects can also be created by calls of the form
     'new("itemsets", ...)'.

_S_l_o_t_s:

     '_i_t_e_m_s': object of class 'itemMatrix' containing the  items in the
          set of itemsets

     '_q_u_a_l_i_t_y': object of class '"data.frame"' containing the quality
          measures for the itemsets

     '_t_i_d_L_i_s_t': object of class 'tidList' containing the IDs of the
          transactions which support each itemset.  The slot contains
          'NULL' if no transactions ID list is available (transactions
          ID lists are only available for 'eclat').

_E_x_t_e_n_d_s:

     Class 'associations', directly.

_M_e_t_h_o_d_s:

     [ 'signature(x = "itemsets")'; extracts a subset of itemsets and
          the associated quality measures

     _c_o_e_r_c_e 'signature(from = "itemsets", to = "data.frame")';
          represent the itemsets in readable form

     _i_t_e_m_s 'signature(x = "itemsets")'; returns the 'itemMatrix'
          representing the set of itemsets

     _i_t_e_m_s<- 'signature(x = "itemsets")'; replaces the 'itemMatrix'
          representing the set of itemsets

     _i_t_e_m_I_n_f_o 'signature(object = "itemsets")';  returns the whole item
          information data frame including item labels

     _l_a_b_e_l_s 'signature(object = "itemsets")'; returns labels for the
          itemsets ("{items}") as a 'character' vector

     _l_e_n_g_t_h 'signature(x = "itemsets")'; returns the number of itemsets
          stored in the the set

     _s_u_b_s_e_t 'signature(x = "itemsets")'; select a subset of itemsets
          using restrictions on the quality measures or on the items
          present in the itemsets

     _s_u_m_m_a_r_y 'signature(object = "itemsets")'

     _t_i_d_L_i_s_t 'signature(object = "itemsets")'; returns the transaction
          ID list

_A_u_t_h_o_r(_s):

     Michael Hahsler

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

     'eclat', 'apriori', 'associations-class',  'tidList-class'

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

     data("Adult_transactions")

     ## Mine frequent itemsets with Eclat.
     fsets <- eclat(Adult_transactions, parameter = list(supp = 0.5))

     ## Display the 5 itemsets with the highest support.
     inspect(SORT(fsets)[1:5])

