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

186 HP MLIB User’s Guide
F_SNORM/F_DNORM Norm of a vector
Input NORM Specifies the norm to compute. Seven distinct values
are possible, namely the 1-norm, real 1-norm,
infinity-norm, and real infinity-norm for vectors and
matrices, the 2-norm for vectors, and the
Frobenius-norm, max-norm, and real max-norm for
matrices. Use one of the following constants:
BLAS_ONE_NORM BLAS_REAL_ONE_NORM
BLAS_INF_NORM BLAS_REAL_INF_NORM
BLAS_TWO_NORM BLAS_FROBENIUS_NORM
BLAS_MAX_NORM BLAS_REAL_MAX_NORM
When you specify NORM = BLAS_FROBENIUS_NORM,
an error flag is not raised, and the routine returns the
two-norm.
N Number of elements of vector x.
X REAL array, minimum length (N-1) x |incx|+ 1.
INCX Increment for the array x. A vector x having component
x
i
, i = 1,..., n, is stored in an array X() with increment
argument incx. If incx > 0 then x
i
is stored in
X (1 + (i - 1) x incx). If incx < 0 then x
i
is stored in
X (1 + (N - i) x |incx|). incx = 0 is an illegal value.