1SLANSP(1)           LAPACK auxiliary routine (version 3.2)           SLANSP(1)
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NAME

6       SLANSP  -  returns the value of the one norm, or the Frobenius norm, or
7       the infinity norm, or the element of largest absolute value of  a  real
8       symmetric matrix A, supplied in packed form
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SYNOPSIS

11       REAL FUNCTION SLANSP( NORM, UPLO, N, AP, WORK )
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13           CHARACTER NORM, UPLO
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15           INTEGER   N
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17           REAL      AP( * ), WORK( * )
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PURPOSE

20       SLANSP   returns  the value of the one norm,  or the Frobenius norm, or
21       the  infinity norm,  or the  element of  largest absolute value   of  a
22       real symmetric matrix A,  supplied in packed form.
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DESCRIPTION

25       SLANSP returns the value
26          SLANSP = ( max(abs(A(i,j))), NORM = 'M' or 'm'
27                   (
28                   ( norm1(A),         NORM = '1', 'O' or 'o'
29                   (
30                   ( normI(A),         NORM = 'I' or 'i'
31                   (
32                   (  normF(A),          NORM  =  'F',  'f',  'E' or 'e' where
33       norm1  denotes the  one norm of a matrix (maximum  column  sum),  normI
34       denotes  the   infinity  norm  of a matrix  (maximum row sum) and normF
35       denotes the  Frobenius  norm  of  a  matrix  (square  root  of  sum  of
36       squares).   Note  that   max(abs(A(i,j)))   is  not a consistent matrix
37       norm.
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ARGUMENTS

40       NORM    (input) CHARACTER*1
41               Specifies the value to  be  returned  in  SLANSP  as  described
42               above.
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44       UPLO    (input) CHARACTER*1
45               Specifies  whether  the  upper  or lower triangular part of the
46               symmetric matrix A is supplied.  = 'U':  Upper triangular  part
47               of A is supplied
48               = 'L':  Lower triangular part of A is supplied
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50       N       (input) INTEGER
51               The  order of the matrix A.  N >= 0.  When N = 0, SLANSP is set
52               to zero.
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54       AP      (input) REAL array, dimension (N*(N+1)/2)
55               The upper or lower triangle of the symmetric matrix  A,  packed
56               columnwise  in  a linear array.  The j-th column of A is stored
57               in the array AP as follows: if UPLO = 'U', AP(i + (j-1)*j/2)  =
58               A(i,j)  for  1<=i<=j;  if  UPLO = 'L', AP(i + (j-1)*(2n-j)/2) =
59               A(i,j) for j<=i<=n.
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61       WORK    (workspace) REAL array, dimension (MAX(1,LWORK)),
62               where LWORK >= N when NORM = 'I' or '1' or 'O'; otherwise, WORK
63               is not referenced.
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67 LAPACK auxiliary routine (versionNo3v.e2m)ber 2008                       SLANSP(1)
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