HP MLIB User's Guide Vol. 1 7th Ed.

Chapter 4 Sparse BLAS Operations 523
Skyline matrix-matrix multiply SSKYMM/DSKYMM/CSKYMM/ZSKYMM
1: Operate with transpose matrix
2: Operate with conjugate-transpose matrix
m Number of rows in matrix A.
n Number of columns in matrix C.
k Number of columns in matrix A.
alpha Scalar parameter.
descra( )
Descriptor argument. Five element integer array.
descra(1) Matrix structure.
0: General
1: Symmetric
2: Hermitian
3: Triangular
4: Skew (Anti)-Symmetric
5: Diagonal
descra(2) Upper/Lower triangular indicator.
1: Lower
2: Upper
descra(3) Main diagonal type.
0: Non-unit
1: Unit
descra(4) Array base.
0: C/C++ compatible Not Supported
1: Fortran compatible
descra(5) Repeated indices.
0: Unknown
1: No repeated indices
val( ) Array of length pntr(m+1)-1 (see below for pntr)
containing all the nonzero entries, and maybe some
zero entries of A. A must be a square triangular matrix
(m=k). val( ) is row-oriented if A is a lower triangular
matrix (descra(2)=1) and column oriented if A is an