1CLANSP(1) LAPACK auxiliary routine (version 3.1) CLANSP(1)
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6 CLANSP - the value of the one norm, or the Frobenius norm, or the
7 infinity norm, or the element of largest absolute value of a complex
8 symmetric matrix A, supplied in packed form
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11 REAL FUNCTION CLANSP( 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 WORK( * )
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19 COMPLEX AP( * )
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22 CLANSP returns the value of the one norm, or the Frobenius norm, or
23 the infinity norm, or the element of largest absolute value of a
24 complex symmetric matrix A, supplied in packed form.
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28 CLANSP returns the value
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30 CLANSP = ( max(abs(A(i,j))), NORM = 'M' or 'm'
31 (
32 ( norm1(A), NORM = '1', 'O' or 'o'
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34 ( normI(A), NORM = 'I' or 'i'
35 (
36 ( normF(A), NORM = 'F', 'f', 'E' or 'e'
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38 where norm1 denotes the one norm of a matrix (maximum column sum),
39 normI denotes the infinity norm of a matrix (maximum row sum) and
40 normF denotes the Frobenius norm of a matrix (square root of sum of
41 squares). Note that max(abs(A(i,j))) is not a consistent matrix
42 norm.
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46 NORM (input) CHARACTER*1
47 Specifies the value to be returned in CLANSP as described
48 above.
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50 UPLO (input) CHARACTER*1
51 Specifies whether the upper or lower triangular part of the
52 symmetric matrix A is supplied. = 'U': Upper triangular part
53 of A is supplied
54 = 'L': Lower triangular part of A is supplied
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56 N (input) INTEGER
57 The order of the matrix A. N >= 0. When N = 0, CLANSP is set
58 to zero.
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60 AP (input) COMPLEX array, dimension (N*(N+1)/2)
61 The upper or lower triangle of the symmetric matrix A, packed
62 columnwise in a linear array. The j-th column of A is stored
63 in the array AP as follows: if UPLO = 'U', AP(i + (j-1)*j/2) =
64 A(i,j) for 1<=i<=j; if UPLO = 'L', AP(i + (j-1)*(2n-j)/2) =
65 A(i,j) for j<=i<=n.
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67 WORK (workspace) REAL array, dimension (MAX(1,LWORK)),
68 where LWORK >= N when NORM = 'I' or '1' or 'O'; otherwise, WORK
69 is not referenced.
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73 LAPACK auxiliary routine (versionNo3v.e1m)ber 2006 CLANSP(1)