makeContrasts             package:limma             R Documentation

_C_o_n_s_t_r_u_c_t _M_a_t_r_i_x _o_f _C_u_s_t_o_m _C_o_n_t_r_a_s_t_s

_D_e_s_c_r_i_p_t_i_o_n:

     Construct the contrasts matrix corresponding to specified
     contrasts of a set of given parameters.

_U_s_a_g_e:

     makeContrasts(..., levels) 

_A_r_g_u_m_e_n_t_s:

     ...: expressions, or character strings which can be parsed to
          expressions, specifying contrasts

  levels: character vector giving the names of the parameters to be
          contrasts, or a factor or design matrix from which the names
          can be extracted.

_V_a_l_u_e:

     Matrix which columns corresponding to contrasts.

_A_u_t_h_o_r(_s):

     Gordon Smyth

_S_e_e _A_l_s_o:

     An overview of linear model functions in limma is given by
     5.LinearModels.

_E_x_a_m_p_l_e_s:

     makeContrasts(B-A,C-B,C-A,levels=c("A","B","C"))
     makeContrasts("A","B","B-A",levels=c("A","B"))

