pdConstruct.pdBlocked package:nlme R Documentation _C_o_n_s_t_r_u_c_t _p_d_B_l_o_c_k_e_d _O_b_j_e_c_t_s _D_e_s_c_r_i_p_t_i_o_n: This function give an alternative constructor for the 'pdBlocked' class, representing a positive-definite block-diagonal matrix. Each block-diagonal element of the underlying matrix is itself a positive-definite matrix and is represented internally as an individual 'pdMat' object. When 'value' is 'numeric(0)', a list of uninitialized 'pdMat' objects, a list of one-sided formulas, or a list of vectors of character strings, 'object' is returned as an uninitialized 'pdBlocked' object (with just some of its attributes and its class defined) and needs to have its coefficients assigned later, generally using the 'coef' or 'matrix' replacement functions. If 'value' is a list of initialized 'pdMat' objects, 'object' will be constructed from the list obtained by applying 'as.matrix' to each of the 'pdMat' elements of 'value'. Finally, if 'value' is a list of numeric vectors, they are assumed to represent the unrestricted coefficients of the block-diagonal elements of the underlying positive-definite matrix. _U_s_a_g_e: ## S3 method for class 'pdBlocked': pdConstruct(object, value, form, nam, data, pdClass, ...) _A_r_g_u_m_e_n_t_s: object: an object inheriting from class 'pdBlocked', representing a positive definite block-diagonal matrix. value: an optional list with elements to be used as the 'value' argument to other 'pdMat' constructors. These include: 'pdMat' objects, positive-definite matrices, one-sided linear formulas, vectors of character strings, or numeric vectors. All elements in the list must be similar (e.g. all one-sided formulas, or all numeric vectors). Defaults to 'numeric(0)', corresponding to an uninitialized object. form: an optional list of one-sided linear formula specifying the row/column names for the block-diagonal elements of the matrix represented by 'object'. Because factors may be present in 'form', the formulas needs to be evaluated on a data.frame to resolve the names they defines. This argument is ignored when 'value' is a list of one-sided formulas. Defaults to 'NULL'. nam: an optional list of vector of character strings specifying the row/column names for the block-diagonal elements of the matrix represented by object. Each of its components must have length equal to the dimension of the corresponding block-diagonal element and unreplicated elements. This argument is ignored when 'value' is a list of vector of character strings. Defaults to 'NULL'. data: an optional data frame in which to evaluate the variables named in 'value' and 'form'. It is used to obtain the levels for 'factors', which affect the dimensions and the row/column names of the underlying matrix. If 'NULL', no attempt is made to obtain information on 'factors' appearing in the formulas. Defaults to the parent frame from which the function was called. pdClass: an optional vector of character strings naming the 'pdMat' classes to be assigned to the individual blocks in the underlying matrix. If a single class is specified, it is used for all block-diagonal elements. This argument will only be used when 'value' is missing, or its elements are not 'pdMat' objects. Defaults to '"pdSymm"'. ...: some methods for this generic require additional arguments. None are used in this method. _V_a_l_u_e: a 'pdBlocked' object representing a positive-definite block-diagonal matrix, also inheriting from class 'pdMat'. _A_u_t_h_o_r(_s): Jose Pinheiro Jose.Pinheiro@pharma.novartis.com and Douglas Bates bates@stat.wisc.edu _R_e_f_e_r_e_n_c_e_s: Pinheiro, J.C., and Bates, D.M. (2000) "Mixed-Effects Models in S and S-PLUS", Springer. _S_e_e _A_l_s_o: 'as.matrix.pdMat', 'coef.pdMat', 'pdBlocked', 'pdClasses', 'pdConstruct', 'matrix<-.pdMat' _E_x_a_m_p_l_e_s: pd1 <- pdBlocked(list(c("A","B"), c("a1", "a2", "a3"))) pdConstruct(pd1, list(diag(1:2), diag(c(0.1, 0.2, 0.3))))