ttdd.cc

LAPACK++ (Linear Algebra PACKage in C++) is a software library for numerical linear algebra that sol

//
//              LAPACK++ 1.1 Linear Algebra Package 1.1
//               University of Tennessee, Knoxvilee, TN.
//            Oak Ridge National Laboratory, Oak Ridge, TN.
//        Authors: J. J. Dongarra, E. Greaser, R. Pozo, D. Walker
//                 (C) 1992-1996 All Rights Reserved
//
//                             NOTICE
//
// Permission to use, copy, modify, and distribute this software and
// its documentation for any purpose and without fee is hereby granted
// provided that the above copyright notice appear in all copies and
// that both the copyright notice and this permission notice appear in
// supporting documentation.
//
// Neither the Institutions (University of Tennessee, and Oak Ridge National
// Laboratory) nor the Authors make any representations about the suitability 
// of this software for any purpose.  This software is provided ``as is'' 
// without express or implied warranty.
//
// LAPACK++ was funded in part by the U.S. Department of Energy, the
// National Science Foundation and the State of Tennessee.


#include <stdlib.h>
#include "lafnames.h"
#include LA_TRIDIAG_MAT_DOUBLE_H
#include "latmpl.h"
#include "trfd.h"


using namespace std;

bool test_diagassign(int M)
{
   double alpha=1.5;
   bool all_ok = true;
   LaVectorDouble x(M), b(M), Diag(M), DiagL(M-1), DiagU(M-1);
   for (int i=0; i< M; i++)
      Diag(i)=1+2*alpha*0;
   for (int i=0; i< M-1; i++)
      DiagL(i)=-3*alpha;
   for (int i=0; i< M-1; i++)
      DiagU(i)=-alpha;

   cout << "Testing assignment to tridiag matrix. DiagL= ";
   cout << DiagL << endl;
   LaTridiagMatDouble Mat(M);
   Mat.diag(0)=Diag;
   Mat.diag(-1).inject(DiagL);
   Mat.diag(1)=DiagU;
   //for (int i=0; i< M-1; i++)
   //cout << Diag(i) << endl;
   cout << "and Mat = " << Mat << endl;
   cout << "and Mat(0,0) = " << Mat(0,0) << endl;

   cout << "and Mat=" << endl;
   for (int i = 0; i < M; ++i) {
      for (int j = 0; j < M; ++j)
	 if (i-j < -1 || i-j > 1)
	    cout << " * ";
	 else
	    cout << Mat(i,j) << " ";
      cout << endl;
   }

   if (Mat(0,0) != Diag(0)) all_ok = false;

   // define X and B
   LaGenMatDouble B(M,1);
   la::rand(B); // fill B with values from somewhere
   // To solve Ax=b:
   LaTridiagFactDouble Afact;
   LaGenMatDouble X(M,1);
   LaTridiagMatFactorize(Mat, Afact); // calculate LU factorization
   LaLinearSolve(Afact, X, B); // solve; result is in X

   return all_ok;
}


int main(int argc, char *argv[])
{
    int N;
    bool okay = true;

    if (argc < 2)
    {
         std::cerr << "Usage:  " << argv[0] << " N " << std::endl;
         exit(1);
    }

    N = atoi(argv[1]);

    // Test constructors
    //
    LaTridiagMatDouble A;
    std::cout << std::endl << "null consturctor " << std::endl;
    std::cout << "A:\n" << A.info() << std::endl;

    std::cout << std::endl;
    LaTridiagMatDouble C(N);
    std::cout << std::endl << "(int, int) constructor " << std::endl;
    std::cout << "C(N):\n" << C.info() << std::endl;

    std::cout << std::endl;
    std::cout << " &C(0,0): " << (long) &C(0,0) << std::endl;

    std::cout << std::endl;
    LaTridiagMatDouble D(C);        // D is also N,N
    std::cout << std::endl << "X(const &X) constructor " << std::endl;
    std::cout << "D(C):\n" << D.info() << std::endl;

    std::cout << std::endl;
    std::cout << "test A.ref(C)\n";
    A.ref(C);
    std::cout << "A:\n" << A.info() << std::endl;

    std::cout << "D.diag(0) = 3.3" << std::endl;

    D.diag(0) = 3.3;
   
    std::cout << std::endl;
    std::cout << "D:\n" << D << std::endl;

    std::cout << std::endl;
    std::cout << "test A.copy(D)\n";
    A.copy(D);
    std::cout << "A:\n" << A.info() << std::endl;
    std::cout << "A:\n" << A << std::endl;
    

    LaVectorDouble tmp(3*N-2);
    tmp(LaIndex(0,N-2)) = 9.9;

    C.diag(-1)(LaIndex(0,N-2)) = 1.1;
    std::cout << "\nC:\n" << C << std::endl;
    
    C.diag(-1)(LaIndex(0,N-2)) = tmp(LaIndex(0,N-2));
    std::cout << std::endl;
    std::cout << "test C.diag(-1)(LaIndex(0,N-2)) = tmp(LaIndex(0,N-2))\n";
    std::cout << "\nC:\n" << C << std::endl;
    std::cout << std::endl;

//     std::cout << "\ntest error message: C.diag(3))\n";
//     C.diag(3) = 5.0;
//     std::cout << std::endl;

    okay = okay && test_diagassign(N);

    return okay ? 0 : -1;
}