dpotf2

STD.BLAS.dpotf2( tri,, r, A, clear);

triIndicates whether upper or lower triangle is used
rNumber of rows/columns in the square matrix
AThe square matrix A
clearClears the unused triangle
Return:The triangular matrix requested

The dpotf2 function computes the Cholesky factorization of a real symmetric positive definite matrix A. The factorization has the form A = U**T*U if the tri parameter is Triangle.Upper, or A = L * L**T if the tri parameter is Triangle.Lower. This is the unblocked version of the algorithm, calling Level 2 BLAS.

Example:

IMPORT STD;
STD.BLAS.Types.matrix_t  symmetric_pos_def := [4, 6, 8, 6, 13, 18, 8, 18, 29];
Lower_Triangle := BLAS.dpotf2(STD.BLAS.Types.Triangle.lower, 3, symmetric_pos_def);