1ZLANGE(1)           LAPACK auxiliary routine (version 3.1)           ZLANGE(1)
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NAME

6       ZLANGE  -  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       matrix A
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SYNOPSIS

11       DOUBLE PRECISION FUNCTION ZLANGE( NORM, M, N, A, LDA, WORK )
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13           CHARACTER    NORM
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15           INTEGER      LDA, M, N
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17           DOUBLE       PRECISION WORK( * )
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19           COMPLEX*16   A( LDA, * )
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PURPOSE

22       ZLANGE   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 matrix A.
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DESCRIPTION

28       ZLANGE returns the value
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30          ZLANGE = ( max(abs(A(i,j))), NORM = 'M' or 'm'
31                   (
32                   ( norm1(A),         NORM = '1', 'O' or 'o'
33                   (
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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ARGUMENTS

46       NORM    (input) CHARACTER*1
47               Specifies  the  value  to  be  returned  in ZLANGE as described
48               above.
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50       M       (input) INTEGER
51               The number of rows of the matrix A.  M  >=  0.   When  M  =  0,
52               ZLANGE is set to zero.
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54       N       (input) INTEGER
55               The  number  of  columns of the matrix A.  N >= 0.  When N = 0,
56               ZLANGE is set to zero.
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58       A       (input) COMPLEX*16 array, dimension (LDA,N)
59               The m by n matrix A.
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61       LDA     (input) INTEGER
62               The leading dimension of the array A.  LDA >= max(M,1).
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64       WORK    (workspace) DOUBLE PRECISION array, dimension (MAX(1,LWORK)),
65               where LWORK >= M when NORM = 'I'; otherwise, WORK is not refer‐
66               enced.
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70 LAPACK auxiliary routine (versionNo3v.e1m)ber 2006                       ZLANGE(1)