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

6       ZLANTP  -  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 trian‐
8       gular matrix A, supplied in packed form
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SYNOPSIS

11       DOUBLE PRECISION FUNCTION ZLANTP( NORM, UPLO, DIAG, N, AP, WORK )
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13           CHARACTER    DIAG, NORM, UPLO
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15           INTEGER      N
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17           DOUBLE       PRECISION WORK( * )
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19           COMPLEX*16   AP( * )
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PURPOSE

22       ZLANTP   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       triangular matrix A, supplied in packed form.
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DESCRIPTION

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

42       NORM    (input) CHARACTER*1
43               Specifies the value to  be  returned  in  ZLANTP  as  described
44               above.
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46       UPLO    (input) CHARACTER*1
47               Specifies whether the matrix A is upper or lower triangular.  =
48               'U':  Upper triangular
49               = 'L':  Lower triangular
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51       DIAG    (input) CHARACTER*1
52               Specifies whether or not the matrix A is  unit  triangular.   =
53               'N':  Non-unit triangular
54               = 'U':  Unit triangular
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56       N       (input) INTEGER
57               The  order of the matrix A.  N >= 0.  When N = 0, ZLANTP is set
58               to zero.
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60       AP      (input) COMPLEX*16 array, dimension (N*(N+1)/2)
61               The upper or lower triangular matrix A, packed columnwise in  a
62               linear  array.   The j-th column of A is stored in the array AP
63               as follows: if UPLO = 'U',  AP(i  +  (j-1)*j/2)  =  A(i,j)  for
64               1<=i<=j;  if  UPLO  =  'L', AP(i + (j-1)*(2n-j)/2) = A(i,j) for
65               j<=i<=n.  Note that when DIAG = 'U', the elements of the  array
66               AP  corresponding  to the diagonal elements of the matrix A are
67               not referenced, but are assumed to be one.
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69       WORK    (workspace) DOUBLE PRECISION array, dimension (MAX(1,LWORK)),
70               where LWORK >= N when NORM = 'I'; otherwise, WORK is not refer‐
71               enced.
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75 LAPACK auxiliary routine (versionNo3v.e2m)ber 2008                       ZLANTP(1)
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