groupparts           package:compositions           R Documentation

_G_r_o_u_p _a_m_o_u_n_t_s _o_f _p_a_r_t_s

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

     Groups parts by amalgamation or balancing of their amounts or
     proportions.

_U_s_a_g_e:

     groupparts(x,...)
     ## S3 method for class 'acomp':
     groupparts(x,...,groups=list(...))
     ## S3 method for class 'rcomp':
     groupparts(x,...,groups=list(...))
     ## S3 method for class 'aplus':
     groupparts(x,...,groups=list(...))
     ## S3 method for class 'rplus':
     groupparts(x,...,groups=list(...))
               

_A_r_g_u_m_e_n_t_s:

       x: an amount/compositional dataset

     ...: further parameters to use (actually ignored)

  groups: a list of numeric xor character vectors, each giving a group
          of parts

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

     In the real geometry grouping is done by amalgamation (i.e. adding
     the parts). In the Aitchison-geometry grouping is done by taking
     geometric means. The new parts are named by named formal
     arguments. Not-mentioned parts remain ungrouped.

_V_a_l_u_e:

     a new dataset of the same type with each group represented by a
     single column

_R_e_f_e_r_e_n_c_e_s:

     Egozcue, J.J. and V. Pawlowsky-Glahn (2005) Groups of Parts and
     their Balances in Compositional Data Analysis, Mathematical
     Geology, in press

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

     'aplus'

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

     data(SimulatedAmounts)
     groupparts(acomp(sa.lognormals5),A=c(1,2),B=c(3,4),C=5)
     groupparts(aplus(sa.lognormals5),B=c(3,4),C=5)
     groupparts(rcomp(sa.lognormals5),A=c("Cu","Pb"),B=c(2,5))
     groupparts(rplus(sa.lognormals5),1:5)

