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NAME
     dlange - 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 matrix A

SYNOPSIS
     DOUBLE PRECISION FUNCTION DLANGE( NORM, M, N, A, LDA, WORK )

     CHARACTER NORM

     INTEGER LDA, M, N

     DOUBLE PRECISION A( LDA, * ), WORK( * )



     #include <sunperf.h>

     double dlange(char norm, int m, int n, double *da, int lda )
               ;

PURPOSE
     DLANGE  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 matrix A.


DESCRIPTION
     DLANGE returns the value

        DLANGE = ( 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  DLANGE  as
               described above.

     M         (input) INTEGER
               The number of rows of the matrix A.  M >= 0.  When
               M = 0, DLANGE is set to zero.

     N         (input) INTEGER
               The number of columns of the matrix A.   N  >=  0.
               When N = 0, DLANGE is set to zero.

     A         (input) DOUBLE PRECISION array, dimension (LDA,N)
               The m by n matrix A.

     LDA       (input) INTEGER
               The leading dimension of  the  array  A.   LDA  >=
               max(M,1).

     WORK      (workspace)  DOUBLE  PRECISION  array,   dimension
               (LWORK),
               where LWORK >= M when NORM = 'I'; otherwise,  WORK
               is not referenced.

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