PivotData

 Subroutine PivotData do pivotting to the input addmittance matrix. Two
 pivotting will be done: 1. columns and rows corresponding to external
 buses will be pivotted to the top left corner of the input matrix. 2.
 Tinney One optimal ordering strategy will be applied to pivot the data in
 order to reduce fills during (Partial) LU factorization.

   [DataB,ERP,CIndx,PivOrd,PivInd] = PivotData(DataB,ERP,CIndx,ExBus,NUMB,BoundBus)

 INPUT DATA:
   DataB: 1*n array, includes addmittance data of the full model before
   pivotting
   ERP: 1*n array, includes end of row pointer before pivotting
   CIndx: 1*n array, includes column index pointer before pivotting
   ExBus: 1*n array, includes external bus indices in internal numbering
   NUMB: 1*n array, includes bus numbers in internal numbering

 OUTPUT DATA:
   DataB: 1*n array, includes pivotted addmittance data of the full model
   ERP: 1*n array, includes end of row pointer before pivotting
   CIndx: 1*n array, includes column index pointer
   PivOrd: 1*n array, includes bus indices after pivotting
   PivInd: 1*n array, includes bus ordering after pivotting

0001 function [DataB,ERP,CIndx,PivOrd,PivInd] = PivotData(DataB,ERP,CIndx,ExBus,NUMB,BoundBus)
0002 % Subroutine PivotData do pivotting to the input addmittance matrix. Two
0003 % pivotting will be done: 1. columns and rows corresponding to external
0004 % buses will be pivotted to the top left corner of the input matrix. 2.
0005 % Tinney One optimal ordering strategy will be applied to pivot the data in
0006 % order to reduce fills during (Partial) LU factorization.
0007 %
0008 %   [DataB,ERP,CIndx,PivOrd,PivInd] = PivotData(DataB,ERP,CIndx,ExBus,NUMB,BoundBus)
0009 %
0010 % INPUT DATA:
0011 %   DataB: 1*n array, includes addmittance data of the full model before
0012 %   pivotting
0013 %   ERP: 1*n array, includes end of row pointer before pivotting
0014 %   CIndx: 1*n array, includes column index pointer before pivotting
0015 %   ExBus: 1*n array, includes external bus indices in internal numbering
0016 %   NUMB: 1*n array, includes bus numbers in internal numbering
0017 %
0018 % OUTPUT DATA:
0019 %   DataB: 1*n array, includes pivotted addmittance data of the full model
0020 %   ERP: 1*n array, includes end of row pointer before pivotting
0021 %   CIndx: 1*n array, includes column index pointer
0022 %   PivOrd: 1*n array, includes bus indices after pivotting
0023 %   PivInd: 1*n array, includes bus ordering after pivotting
0024 
0025 %   MATPOWER
0026 %   Copyright (c) 2014-2015 by Power System Engineering Research Center (PSERC)
0027 %   by Yujia Zhu, PSERC ASU
0028 %
0029 %   $Id: PivotData.m 2655 2015-03-18 16:40:32Z ray $
0030 %
0031 %   This file is part of MATPOWER.
0032 %   Covered by the 3-clause BSD License (see LICENSE file for details).
0033 %   See http://www.pserc.cornell.edu/matpower/ for more info.
0034 
0035 DataBO = zeros(size(DataB));
0036 CIndxO = zeros(size(CIndx));
0037 ERPO = zeros(size(ERP));
0038 
0039 % do pivot
0040 ExBus = sort(ExBus);
0041 tf1 = ismember(NUMB,ExBus);
0042 tf2 = ismember(NUMB,BoundBus);
0043 PivInd = [sort(NUMB(tf1==1))',sort(NUMB(tf2==1))',sort(NUMB(tf1==0&tf2==0))'];
0044 PivOrd = zeros(size(PivInd));
0045 
0046 for i = 1:length(PivInd)
0047     PivOrd(PivInd(i))=i;
0048 end
0049 
0050 %% Do Tinnney One ordering to reduce fills
0051 [PivOrd,PivInd] = TinneyOne(ERP,PivInd,PivOrd,ExBus);
0052 
0053 %% Generate the datas in compact storage format
0054 for i = 1:length(NUMB)
0055     len = ERP(PivInd(i)+1)-ERP(PivInd(i));
0056     ERPO(i+1)=ERPO(i)+len;
0057     CIndxO((ERPO(i)+1):ERPO(i+1))=PivOrd(CIndx(ERP(PivInd(i))+1:ERP(PivInd(i)+1)));
0058     DataBO((ERPO(i)+1):ERPO(i+1))=DataB(ERP(PivInd(i))+1:ERP(PivInd(i)+1));
0059 end
0060 
0061 %% Generate the output data
0062 DataB = DataBO;
0063 CIndx = CIndxO;
0064 ERP = ERPO;
0065 
0066 end