SRC/dlansp.f(3)            Library Functions Manual            SRC/dlansp.f(3)

NAME
       SRC/dlansp.f

SYNOPSIS
   Functions/Subroutines
       double precision function dlansp (norm, uplo, n, ap, work)
           DLANSP returns the value of the 1-norm, or the Frobenius norm, or
           the infinity norm, or the element of largest absolute value of a
           symmetric matrix supplied in packed form.

Function/Subroutine Documentation
   double precision function dlansp (character norm, character uplo, integer
       n, double precision, dimension( * ) ap, double precision, dimension( *
       ) work)
       DLANSP returns the value of the 1-norm, or the Frobenius norm, or the
       infinity norm, or the element of largest absolute value of a symmetric
       matrix supplied in packed form.

       Purpose:


            DLANSP  returns the value of the one norm,  or the Frobenius norm, or
            the  infinity norm,  or the  element of  largest absolute value  of a
            real symmetric matrix A,  supplied in packed form.

       Returns
           DLANSP

               DLANSP = ( max(abs(A(i,j))), NORM = 'M' or 'm'
                        (
                        ( norm1(A),         NORM = '1', 'O' or 'o'
                        (
                        ( normI(A),         NORM = 'I' or 'i'
                        (
                        ( normF(A),         NORM = 'F', 'f', 'E' or 'e'

            where  norm1  denotes the  one norm of a matrix (maximum column sum),
            normI  denotes the  infinity norm  of a matrix  (maximum row sum) and
            normF  denotes the  Frobenius norm of a matrix (square root of sum of
            squares).  Note that  max(abs(A(i,j)))  is not a consistent matrix norm.

       Parameters
           NORM

                     NORM is CHARACTER*1
                     Specifies the value to be returned in DLANSP as described
                     above.

           UPLO

                     UPLO is CHARACTER*1
                     Specifies whether the upper or lower triangular part of the
                     symmetric matrix A is supplied.
                     = 'U':  Upper triangular part of A is supplied
                     = 'L':  Lower triangular part of A is supplied

           N

                     N is INTEGER
                     The order of the matrix A.  N >= 0.  When N = 0, DLANSP is
                     set to zero.

           AP

                     AP is DOUBLE PRECISION array, dimension (N*(N+1)/2)
                     The upper or lower triangle of the symmetric matrix A, packed
                     columnwise in a linear array.  The j-th column of A is stored
                     in the array AP as follows:
                     if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j;
                     if UPLO = 'L', AP(i + (j-1)*(2n-j)/2) = A(i,j) for j<=i<=n.

           WORK

                     WORK is DOUBLE PRECISION array, dimension (MAX(1,LWORK)),
                     where LWORK >= N when NORM = 'I' or '1' or 'O'; otherwise,
                     WORK is not referenced.

       Author
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Definition at line 113 of file dlansp.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

LAPACK                          Version 3.12.0                 SRC/dlansp.f(3)