1ZLANGT(1)           LAPACK auxiliary routine (version 3.2)           ZLANGT(1)
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NAME

6       ZLANGT  -  returns the value of the one norm, or the Frobenius norm, or
7       the infinity norm, or the element of largest absolute value of  a  com‐
8       plex tridiagonal matrix A
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SYNOPSIS

11       DOUBLE PRECISION FUNCTION ZLANGT( NORM, N, DL, D, DU )
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13           CHARACTER    NORM
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15           INTEGER      N
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17           COMPLEX*16   D( * ), DL( * ), DU( * )
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PURPOSE

20       ZLANGT   returns  the value of the one norm,  or the Frobenius norm, or
21       the  infinity norm,  or the  element of  largest absolute value   of  a
22       complex tridiagonal matrix A.
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DESCRIPTION

25       ZLANGT returns the value
26          ZLANGT = ( max(abs(A(i,j))), NORM = 'M' or 'm'
27                   (
28                   ( norm1(A),         NORM = '1', 'O' or 'o'
29                   (
30                   ( normI(A),         NORM = 'I' or 'i'
31                   (
32                   (  normF(A),          NORM  =  'F',  'f',  'E' or 'e' where
33       norm1  denotes the  one norm of a matrix (maximum  column  sum),  normI
34       denotes  the   infinity  norm  of a matrix  (maximum row sum) and normF
35       denotes the  Frobenius  norm  of  a  matrix  (square  root  of  sum  of
36       squares).   Note  that   max(abs(A(i,j)))   is  not a consistent matrix
37       norm.
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ARGUMENTS

40       NORM    (input) CHARACTER*1
41               Specifies the value to  be  returned  in  ZLANGT  as  described
42               above.
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44       N       (input) INTEGER
45               The  order of the matrix A.  N >= 0.  When N = 0, ZLANGT is set
46               to zero.
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48       DL      (input) COMPLEX*16 array, dimension (N-1)
49               The (n-1) sub-diagonal elements of A.
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51       D       (input) COMPLEX*16 array, dimension (N)
52               The diagonal elements of A.
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54       DU      (input) COMPLEX*16 array, dimension (N-1)
55               The (n-1) super-diagonal elements of A.
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59 LAPACK auxiliary routine (versionNo3v.e2m)ber 2008                       ZLANGT(1)
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