1ZLANSY(1) LAPACK auxiliary routine (version 3.1) ZLANSY(1)
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6 ZLANSY - 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
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11 DOUBLE PRECISION FUNCTION ZLANSY( NORM, UPLO, N, A, LDA, WORK )
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13 CHARACTER NORM, UPLO
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15 INTEGER LDA, N
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17 DOUBLE PRECISION WORK( * )
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19 COMPLEX*16 A( LDA, * )
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22 ZLANSY 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.
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28 ZLANSY returns the value
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30 ZLANSY = ( 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'
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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 ZLANSY 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 to be referenced. = 'U': Upper triangu‐
53 lar part of A is referenced
54 = 'L': Lower triangular part of A is referenced
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56 N (input) INTEGER
57 The order of the matrix A. N >= 0. When N = 0, ZLANSY is set
58 to zero.
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60 A (input) COMPLEX*16 array, dimension (LDA,N)
61 The symmetric matrix A. If UPLO = 'U', the leading n by n
62 upper triangular part of A contains the upper triangular part
63 of the matrix A, and the strictly lower triangular part of A is
64 not referenced. If UPLO = 'L', the leading n by n lower trian‐
65 gular part of A contains the lower triangular part of the
66 matrix A, and the strictly upper triangular part of A is not
67 referenced.
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69 LDA (input) INTEGER
70 The leading dimension of the array A. LDA >= max(N,1).
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72 WORK (workspace) DOUBLE PRECISION array, dimension (MAX(1,LWORK)),
73 where LWORK >= N when NORM = 'I' or '1' or 'O'; otherwise, WORK
74 is not referenced.
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78 LAPACK auxiliary routine (versionNo3v.e1m)ber 2006 ZLANSY(1)