potri (USM Version)

Computes the inverse of a symmetric (Hermitian) positive-definite matrix using the Cholesky factorization. This routine belongs to the oneapi::mkl::lapacknamespace.


cl::sycl::event potri(cl::sycl::queue &queue, mkl::uplo uplo, std::int64_t n, T *a, std::int64_t lda, T *scratchpad, std::int64_t scratchpad_size, const cl::sycl::vector_class<cl::sycl::event> &events = {})

potri (USM version) supports the following precisions and devices:


Devices Supported


Host, CPU, GPU


Host, CPU, GPU


Host, CPU, GPU


Host, CPU, GPU


The routine computes the inverse inv(A) of a symmetric positive definite or, for complex flavors, Hermitian positive-definite matrix A. Before calling this routine, call potrf (USM Version) to factorize A.

Input Parameters


Device queue where calculations will be performed.


Indicates how the input matrix A has been factored:

If uplo = mkl::uplo::upper, the upper triangle of A is stored.

If uplo = mkl::uplo::lower, the lower triangle of A is stored.


Specifies the order of the matrix A (0≤n).


Contains the factorization of the matrix A, as returned by potrf (USM Version). The second dimension of a must be at least max(1, n).


The leading dimension of a.


Pointer to scratchpad memory to be used by the routine for storing intermediate results.


Size of scratchpad memory as a number of floating point elements of type T. Size should not be less than the value returned by the potri_scratchpad_size function.


List of events to wait for before starting computation. Defaults to empty list.

Output Parameters


Overwritten by the upper or lower triangle of the inverse of A. Specified by uplo.



This exception is thrown when problems occur during calculations. You can obtain the info code of the problem using the info() method of the exception object: If info = -i, the i-th parameter had an illegal value. If info = i, the i-th diagonal element of the Cholesky factor (and therefore the factor itself) is zero, and the inversion could not be completed. If info is equal to the value passed as scratchpad size, and detail() returns non zero, then the passed scratchpad has an insufficient size, and the required size should not be less than the value returned by the detail() method of the exception object.

Return Values

Output event to wait on to ensure computation is complete.