- AB
- (
*input/output*)**REAL**or**COMPLEX**array, shape with (**AB**,1) and (**AB**,2) , where is the number of subdiagonals or superdiagonals in the band and is the order of and .

On entry, the upper (if**UPLO**= 'U') or lower (if**UPLO**= 'L') triangle of matrix in band storage. The diagonals of are stored in the rows of**AB**so that the column of is stored in the column of as follows:

On exit, the contents of

**AB**are destroyed. - BB
- (
*input/output*)**REAL**or**COMPLEX**array, shape with (**BB**,1) and (**BB**,2) , where is the number of subdiagonals or superdiagonals in the band of .

On entry, the upper (if**UPLO**= 'U') or lower (if**UPLO**= 'L') triangle of matrix in band storage. The diagonals of are stored in the rows of**BB**so that the column of is stored in the column of as follows:

On exit, the factor from the split Cholesky factorization . - W
- (
*output*)**REAL**array, shape with (**W**) .

The eigenvalues in ascending order. - UPLO
*Optional*(*input*)**CHARACTER(LEN=1)**.

Default value: 'U'.- Z
*Optional*(*output*)**REAL**or**COMPLEX**square array, shape with (**Z**,1) .

The matrix of eigenvectors, normalized so that .- INFO
*Optional*(*output*)**INTEGER**.

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