If the symmetric matrix *A* is represented by its LDLT-decomposition *A = LDL ^{ T}* (or

As LDLT-decomposition is twice as fast as LU-decomposition which is used to calculate general matrix determinants, it is recommended to use LDLT-decomposition when calculating a determinant of a symmetric matrix. In order to calculate the determinant of a symmetric positive definite matrix algorithm on the basis of Cholesky decomposition can be used.

There are two subroutines in this module. The first subroutine, **SMatrixLDLTDet**, calculates the determinant of a matrix whose LDLT-decomposition has already been generated. The second subroutine, **SMatrixDet**, works with symmetric matrices whose LDLT-decomposition hasn't been generated yet.

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