ex02i_dense_matrix_block_operations.cpp

 
#include <iostream>
#include <cla3p/dense.hpp>
 
int main()
{
    cla3p::dns::RdMatrix A(5, 5);
 
    for(cla3p::uint_t j = 0, icnt = 0; j < 5; j++)
        for(cla3p::uint_t i = 0; i < 5; i++)
            A(i,j) = icnt++;
 
    std::cout << "A:\n" << A << "\n";
 
    /*
     * Get a (2x2) copy of the contents of A starting at (1,2).
     * Get a (3x2) reference of the contents of A starting at (2,0).
     */
    cla3p::dns::RdMatrix Ab = A.block(1, 2, 2, 2);
    cla3p::dns::RdMatrix Ar = A.rblock(2, 0, 3, 2);
    std::cout << "Ab:\n" << Ab;
    std::cout << "Ar:\n" << Ar;
 
    /*
     * Get a (3x2) guarded reference of the contents of Aref starting at (2,0).
     */
    const cla3p::dns::RdMatrix& Aref = A;
    cla3p::Guard<cla3p::dns::RdMatrix> Ag = Aref.rblock(2, 0, 3, 2);
    std::cout << "Ag:\n" << Ag.get() << "\n";
 
    /*
     * Change values in blocks.
     */
    Ar = -1;
    std::cout << "A:\n" << A;
 
    /*
     * Set values of Ab to A, starting at (1,1).
     */
    Ab = -2;
    A.setBlock(1, 1, Ab);
    std::cout << "A:\n" << A;
 
    /*
     * Set values of Ab to A, starting at (2,3).
     */
    Ab = -3;
    A.rblock(2, 3, 2, 2) = Ab;
    std::cout << "A:\n" << A;
 
    return 0;
}