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dlange.f(3)                         LAPACK                         dlange.f(3)

NAME

dlange.f -

SYNOPSIS

Functions/Subroutines DOUBLE PRECISION function dlange (NORM, M, N, A, LDA, WORK) DLANGE returns the value of the 1-norm, Frobenius norm, infinity-norm, or the largest absolute value of any element of a general rectangular matrix. Function/Subroutine Documentation DOUBLE PRECISION function dlange (characterNORM, integerM, integerN, double precision, dimension( lda, * )A, integerLDA, double precision, dimension( * )WORK) DLANGE returns the value of the 1-norm, Frobenius norm, infinity-norm, or the largest absolute value of any element of a general rectangular matrix. 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. Returns: DLANGE 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 consistent matrix norm. Parameters: NORM NORM is CHARACTER*1 Specifies the value to be returned in DLANGE as described above. M M is INTEGER The number of rows of the matrix A. M >= 0. When M = 0, DLANGE is set to zero. N N is INTEGER The number of columns of the matrix A. N >= 0. When N = 0, DLANGE is set to zero. A A is DOUBLE PRECISION array, dimension (LDA,N) The m by n matrix A. LDA LDA is INTEGER The leading dimension of the array A. LDA >= max(M,1). WORK WORK is DOUBLE PRECISION array, dimension (MAX(1,LWORK)), where LWORK >= M when NORM = 'I'; otherwise, WORK is not referenced. Author: Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Date: September 2012 Definition at line 115 of file dlange.f. Author Generated automatically by Doxygen for LAPACK from the source code. Version 3.4.2 Sat Nov 16 2013 dlange.f(3)

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