- A
- (
*input*)**REAL**or**COMPLEX**square array, shape .

The symmetric or Hermitian matrix .

If**UPLO**= 'U', the upper triangular part of**A**contains the upper triangular part of the matrix , and the strictly lower triangular part of**A**is not referenced. If**UPLO**= 'L', the lower triangular part of**A**contains the lower triangular part of the matrix , and the strictly upper triangular part of**A**is not referenced. - B
- (
*input*)**REAL**or**COMPLEX**array, shape with or shape with .

The matrix . - X
- (
*output*)**REAL**or**COMPLEX**array, shape with and , or shape with .

The solution matrix . - UPLO
*Optional*(*input*)**CHARACTER(LEN=1)**.

Default value: 'U'.- AF
*Optional*(*input*or*output*)**REAL**or**COMPLEX**array, shape with the same size as .

If**FACT**= 'F', then**AF**is an*input*argument that contains the block diagonal matrix and the multipliers used to obtain the factor or from the factorization of , returned by a previous call to**LA_SYSVX**or**LA_HESVX**.

If**FACT**= 'N', then**AF**is an*output*argument that contains the block diagonal matrix and the multipliers used to obtain the factor or from the factorization of .- IPIV
*Optional*(*input*or*output*)**INTEGER**array, shape with .

If**FACT**= 'F', then is an*input*argument that contains details of the row and column interchanges and the block structure of .

If**FACT**= 'N', then**IPIV**is an*output*argument that contains details of the row and column interchanges and the block structure of ; as described above.- FACT
*Optional*(*input*)**CHARACTER(LEN=1)**.

Specifies whether the factored form of the matrix has been supplied on entry.

Default value: 'N'.- FERR
*Optional*(*output*)**REAL**array of shape , with , or**REAL**scalar.

The estimated forward error bound for each solution vector (the column of the solution matrix ). If is the true solution corresponding to , is an estimated upper bound for the magnitude of the largest element in ( divided by the magnitude of the largest element in . The estimate is as reliable as the estimate for , and is almost always a slight overestimate of the true error.- BERR
*Optional*(*output*)**REAL**array of shape , with , or**REAL**scalar.

The componentwise relative backward error of each solution vector (i.e., the smallest relative change in any element of or that makes an exact solution).- RCOND
*Optional*(*output)***REAL**

The estimate of the reciprocal condition number of . If is less than the machine precision, the matrix is singular to working precision. This condition is indicated by a return code of .- INFO
- (
*output*)**INTEGER**

If is not present and an error occurs, then the program is terminated with an error message.