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#include <cusp/dia_matrix.h>
#include <cusp/print.h>
int main(void)
{
// allocate storage for (4,3) matrix with 6 nonzeros in 3 diagonals
cusp::dia_matrix<int,float,cusp::host_memory> A(4,3,6,3);
// initialize diagonal offsets
A.diagonal_offsets[0] = -2;
A.diagonal_offsets[1] = 0;
A.diagonal_offsets[2] = 1;
// initialize diagonal values
// first diagonal
A.values(0,2) = 0; // outside matrix
A.values(1,2) = 0; // outside matrix
A.values(2,0) = 40;
A.values(3,0) = 60;
// second diagonal
A.values(0,1) = 10;
A.values(1,1) = 0;
A.values(2,1) = 50;
A.values(3,1) = 50; // outside matrix
// third diagonal
A.values(0,2) = 20;
A.values(1,2) = 30;
A.values(2,2) = 0; // outside matrix
A.values(3,2) = 0; // outside matrix
// A now represents the following matrix
// [10 20 0]
// [ 0 0 30]
// [40 0 50]
// [ 0 60 0]
// print matrix entries
cusp::print(A);
return 0;
}
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