HP MLIB User's Guide Vol. 2 7th Ed.

672 HP MLIB LAPACK User’s Guide
SLANSP/DLANSP/CLANHP/CLANSP/.../ZLANSP Compute norm of symmetric or Hermitian packed matrix
Lower triangular storage
If the lower triangle of A is
then A is packed column-by-column into an array ap as follows:
Lower triangular matrix element a
ij
is stored in array element
ap(i+((j−1)×(2n−j))/2).
Usage LAPACK:
CHARACTER*1 norm, uplo
INTEGER*4 n
REAL*4 ap((n*(n+1))/2), work(n)
REAL*4 anorm, SLANSP
anorm = SLANSP(norm, uplo, n, ap, work)
CHARACTER*1 norm, uplo
INTEGER*4 n
REAL*8 ap((n*(n+1))/2), work(n)
REAL*8 anorm, DLANSP
anorm = DLANSP(norm, uplo, n, ap, work)
CHARACTER*1 norm, uplo
INTEGER*4 n
REAL*4 rwork(n)
COMPLEX*8 ap((n*(n+1))/2)
REAL*4 anorm, CLANHP
anorm = CLANHP(norm, uplo, n, ap, rwork)
CHARACTER*1 norm, uplo
INTEGER*4 n
REAL*4 rwork(n)
COMPLEX*8 ap((n*(n+1))/2)
REAL*4 anorm, CLANSP
anorm = CLANSP(norm, uplo, n, ap, rwork)
11
21 22
31 32 33
41 42 43 44
k 12345678910
ap(k) 11213141223242334344