function [AREA_I, PRICE_REF_BUS] = idx_area%IDX_AREA   Defines constants for named column indices to areas matrix.%   [AREA_I, PRICE_REF_BUS] = idx_area%%   The index, name and meaning of each column of the areas matrix is given%   below:% %   columns 1-2%    1  AREA_I       	area number%    2  PRICE_REF_BUS	price reference bus for this area%   MATPOWER%   $Id: idx_area.m,v 1.6 2004/12/15 22:46:26 ray Exp $%   by Ray Zimmerman, PSERC Cornell%   Copyright (c) 1996-2004 by Power System Engineering Research Center (PSERC)%   See http://www.pserc.cornell.edu/matpower/ for more info.%% define the indicesAREA_I          = 1;    %% area numberPRICE_REF_BUS   = 2;    %% price reference bus for this areareturn;