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LAPACK
3.7.0
LAPACK: Linear Algebra PACKage
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real function clangt | ( | character | NORM, |
integer | N, | ||
complex, dimension( * ) | DL, | ||
complex, dimension( * ) | D, | ||
complex, dimension( * ) | DU | ||
) |
CLANGT returns the value of the 1-norm, Frobenius norm, infinity-norm, or the largest absolute value of any element of a general tridiagonal matrix.
Download CLANGT + dependencies [TGZ] [ZIP] [TXT]
CLANGT returns the value of the one norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a complex tridiagonal matrix A.
CLANGT = ( 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.
[in] | NORM | NORM is CHARACTER*1 Specifies the value to be returned in CLANGT as described above. |
[in] | N | N is INTEGER The order of the matrix A. N >= 0. When N = 0, CLANGT is set to zero. |
[in] | DL | DL is COMPLEX array, dimension (N-1) The (n-1) sub-diagonal elements of A. |
[in] | D | D is COMPLEX array, dimension (N) The diagonal elements of A. |
[in] | DU | DU is COMPLEX array, dimension (N-1) The (n-1) super-diagonal elements of A. |
Definition at line 108 of file clangt.f.