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NAME
     dlansp - return the value of the one norm, or the  Frobenius
     norm,  or the infinity norm, or the element of largest abso-
     lute 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( * )



     #include <sunperf.h>

     double dlansp(char norm, char uplo, int n, double *ap) ;

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  Frobenius 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,
               DLANSP is set to zero.

     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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