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## dznrm2()

real(wp) function dznrm2 | ( | integer | n,
|  | complex(wp), dimension(*) | x,
|  | integer | incx )

DZNRM2

Purpose:

      !>
      !> DZNRM2 returns the euclidean norm of a vector via the function
      !> name, so that
      !>
      !>    DZNRM2 := sqrt( x**H*x )
      !>

Parameters

  [in]

  N

      !>          N is INTEGER
      !>         number of elements in input vector(s)
      !>

  [in]

  X

      !>          X is COMPLEX*16 array, dimension (N)
      !>         complex vector with N elements
      !>

  [in]

  INCX

      !>          INCX is INTEGER, storage spacing between elements of X
      !>          If INCX > 0, X(1+(i-1)*INCX) = x(i) for 1 <= i <= n
      !>          If INCX < 0, X(1-(n-i)*INCX) = x(i) for 1 <= i <= n
      !>          If INCX = 0, x isn't a vector so there is no need to call
      !>          this subroutine.  If you call it anyway, it will count x(1)
      !>          in the vector norm N times.
      !>

Author
  Edward Anderson, Lockheed Martin

Date
  August 2016

Contributors:
  Weslley Pereira, University of Colorado Denver, USA

Further Details:

      !>
      !>  Anderson E. (2017)
      !>  Algorithm 978: Safe Scaling in the Level 1 BLAS
      !>  ACM Trans Math Softw 44:1--28
      !>  https://doi.org/10.1145/3061665
      !>
      !>  Blue, James L. (1978)
      !>  A Portable Fortran Program to Find the Euclidean Norm of a Vector
      !>  ACM Trans Math Softw 4:15--23
      !>  https://doi.org/10.1145/355769.355771
      !>
      !>