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pgbsv

The pgbsv solver supports the following input types.

  • data type: DSZC
  • index type: std::int32_t, std::int64_t

The pgbsv solves a square real banded distributed matrix with bandwidth \(KL\), \(KU\) using LU decomposition with partial pivoting. The matrix of size \(N\) is stored in a memory block of size \(N*(KL+KU+1)\).

Constructor

There are two template arguments.

  1. data type, e.g., double, float, std::complex<double>, std::complex<float>.
  2. index type, e.g., std::int32_t, std::int64_t.

This solver uses a 1D process grid. It takes a single argument that represents the number of rows in the grid.

C++
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auto solver = pgbsv<double, int>(np_row);

Solving

C++
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constexpr auto N = 6, NRHS = 2, KL = 1, KU = 2;
// storage for the matrices A and B
std::vector<double> A, B;
// ...
// ... storage is populated by some utility on the root process
// ...
const auto info = solver.solve({N, N, KL, KU, A.data()}, {N, NRHS, B.data()});