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slansp.f(3)                         LAPACK                         slansp.f(3)


NAME

       slansp.f -


SYNOPSIS

   Functions/Subroutines
       REAL function slansp (NORM, UPLO, N, AP, WORK)
           SLANSP 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
   REAL function slansp (characterNORM, characterUPLO, integerN, real,
       dimension( * )AP, real, dimension( * )WORK)
       SLANSP 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:

            SLANSP  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:
           SLANSP

               SLANSP = ( 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 SLANSP 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, SLANSP is
                     set to zero.

           AP

                     AP is REAL 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 REAL 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.

       Date:
           September 2012

       Definition at line 115 of file slansp.f.

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

Version 3.4.2                   Sat Nov 16 2013                    slansp.f(3)

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