1HPL_pdlange(3)               HPL Library Functions              HPL_pdlange(3)
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NAME

6       HPL_pdlange - Compute ||A||.
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SYNOPSIS

9       #include "hpl.h"
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11       double  HPL_pdlange(  const  HPL_T_grid  * GRID, const HPL_T_NORM NORM,
12       const int M, const int N, const int NB, const double * A, const int LDA
13       );
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DESCRIPTION

16       HPL_pdlange  returns  the value of the one norm,  or the infinity norm,
17       or the element of largest absolute value of a distributed matrix A:
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20          max(abs(A(i,j))) when NORM = HPL_NORM_A,
21          norm1(A),        when NORM = HPL_NORM_1,
22          normI(A),        when NORM = HPL_NORM_I,
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24       where norm1 denotes the one norm of a matrix (maximum column  sum)  and
25       normI  denotes   the infinity norm of a matrix (maximum row sum).  Note
26       that max(abs(A(i,j))) is not a matrix norm.
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ARGUMENTS

29       GRID    (local input)           const HPL_T_grid *
30               On entry,  GRID  points  to the data structure  containing  the
31               process grid information.
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33       NORM    (global input)          const HPL_T_NORM
34               On  entry,   NORM  specifies  the  value to be returned by this
35               function as described above.
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37       M       (global input)          const int
38               On entry,  M  specifies  the number  of rows of the  matrix  A.
39               M must be at least zero.
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41       N       (global input)          const int
42               On  entry,   N specifies the number of columns of the matrix A.
43               N must be at least zero.
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45       NB      (global input)          const int
46               On entry,  NB specifies the blocking factor used  to  partition
47               and distribute the matrix. NB must be larger than one.
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49       A       (local input)           const double *
50               On  entry,   A  points to an array of dimension  (LDA,LocQ(N)),
51               that contains the local pieces of the distributed matrix A.
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53       LDA     (local input)           const int
54               On entry, LDA specifies the leading dimension of the  array  A.
55               LDA must be at least max(1,LocP(M)).
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SEE ALSO

58       HPL_pdlaprnt (3), HPL_fprintf (3).
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62HPL 2.2                        February 24, 2016                HPL_pdlange(3)
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