DLANSP  -  return the value of the one norm, or the Frobe­
       nius norm, or the infinity norm, or the element of largest
       absolute  value  of a real symmetric matrix A, supplied in
       packed form


SYNOPSIS

       DOUBLE PRECISION FUNCTION DLANSP( NORM, UPLO, N, AP,  WORK
                        )

           CHARACTER    NORM, UPLO

           INTEGER      N

           DOUBLE       PRECISION AP( * ), WORK( * )


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.


DESCRIPTION

       DLANSP returns the value

          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  Frobe­
       nius norm of a matrix (square root  of  sum  of  squares).
       Note that  max(abs(A(i,j)))  is not a  matrix norm.


ARGUMENTS

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

       UPLO    (input) 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       (input) INTEGER
               The order of the matrix A.  N >= 0.  When N  =  0,


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


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