VMS Help FORTRAN, Intrinsic Procedures, xNORM2  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  REAL*4 SNORM2  (n, x, incx)
  REAL*8 DNORM2  (n, x, incx)
  REAL*4 SCNORM2 (n, x, incx)
  REAL*8 DZNORM2 (n, x, incx)

  Functions that return the Euclidean norm of array "x" that is the
  square root of the sum of the squares of the absolute values of the
  array elements.  For the purposes of these routines, the absolute
  value of a complex value is the square root of the sum of the
  squares of the real and imaginary parts.

  Unlike the BLAS1 routines xNRM2, the xNORM2 routines assume that
  intermediate underflow or overflow exceptions will not occur.

  These routines are part of the BLAS1 Extended Set, and are
  available only on VAX processors.  The Compaq Extended Math
  Library product may be needed to resolve references to Extended Set
  routines that are not expanded inline by the compiler.

  Arguments

    n

    Integer number of elements in array "x" to be accessed.

    x

    Array containing the elements to be accessed or array reference
    to the first such element.  The data type is REAL*4 for SNORM2,
    REAL*8 for DNORM2, COMPLEX*8 for SCNORM2, COMPLEX*16 for DZNORM2.

    incx

    Integer index increment used in selecting which elements of array
    "x" are accessed.