NAG CL Interface
f16qfc (dge_​copy)

Settings help

CL Name Style:


1 Purpose

f16qfc copies a real general matrix.

2 Specification

#include <nag.h>
void  f16qfc (Nag_OrderType order, Nag_TransType trans, Integer m, Integer n, const double a[], Integer pda, double b[], Integer pdb, NagError *fail)
The function may be called by the names: f16qfc, nag_blast_dge_copy or nag_dge_copy.

3 Description

f16qfc performs the matrix-copy operation
BA   or   BAT  
where A is an m×n rectangular matrix and so is B unless A is to be transposed, in which case B is n×m.

4 References

Basic Linear Algebra Subprograms Technical (BLAST) Forum (2001) Basic Linear Algebra Subprograms Technical (BLAST) Forum Standard University of Tennessee, Knoxville, Tennessee https://www.netlib.org/blas/blast-forum/blas-report.pdf

5 Arguments

1: order Nag_OrderType Input
On entry: the order argument specifies the two-dimensional storage scheme being used, i.e., row-major ordering or column-major ordering. C language defined storage is specified by order=Nag_RowMajor. See Section 3.1.3 in the Introduction to the NAG Library CL Interface for a more detailed explanation of the use of this argument.
Constraint: order=Nag_RowMajor or Nag_ColMajor.
2: trans Nag_TransType Input
On entry: specifies the operation to be performed.
trans=Nag_NoTrans
BA.
trans=Nag_Trans or Nag_ConjTrans
BAT.
Constraint: trans=Nag_NoTrans, Nag_Trans or Nag_ConjTrans.
3: m Integer Input
On entry: m, the number of rows of the matrix A.
Constraint: m0.
4: n Integer Input
On entry: n, the number of columns of the matrix A.
Constraint: n0.
5: a[dim] const double Input
Note: the dimension, dim, of the array a must be at least
  • max(1,pda×n) when order=Nag_ColMajor;
  • max(1,m×pda) when order=Nag_RowMajor.
If order=Nag_ColMajor, Aij is stored in a[(j-1)×pda+i-1].
If order=Nag_RowMajor, Aij is stored in a[(i-1)×pda+j-1].
On entry: the m×n general matrix A.
6: pda Integer Input
On entry: the stride separating row or column elements (depending on the value of order) in the array a.
Constraints:
  • if order=Nag_ColMajor, pdamax(1,m);
  • if order=Nag_RowMajor, pdamax(1,n).
7: b[dim] double Output
Note: the dimension, dim, of the array b must be at least
  • max(1,pdb×n) when trans=Nag_NoTrans and order=Nag_ColMajor;
  • max(1,m×pdb) when trans=Nag_NoTrans and order=Nag_RowMajor;
  • max(1,pdb×m) when trans=Nag_Trans or Nag_ConjTrans and order=Nag_ColMajor;
  • max(1,n×pdb) when trans=Nag_Trans or Nag_ConjTrans and order=Nag_RowMajor.
If order=Nag_ColMajor, Bij is stored in b[(j-1)×pdb+i-1].
If order=Nag_RowMajor, Bij is stored in b[(i-1)×pdb+j-1].
On exit: the matrix B; B is n×k if trans=Nag_NoTrans, or k×n otherwise.
8: pdb Integer Input
On entry: the stride separating row or column elements (depending on the value of order) in the array b.
Constraints:
  • if order=Nag_ColMajor,
    • if trans=Nag_NoTrans, pdbmax(1,m);
    • if trans=Nag_Trans or Nag_ConjTrans, pdbmax(1,n);
  • if order=Nag_RowMajor,
    • if trans=Nag_NoTrans, pdbmax(1,n);
    • if trans=Nag_Trans or Nag_ConjTrans, pdbmax(1,m).
9: fail NagError * Input/Output
The NAG error argument (see Section 7 in the Introduction to the NAG Library CL Interface).

6 Error Indicators and Warnings

NE_ALLOC_FAIL
Dynamic memory allocation failed.
See Section 3.1.2 in the Introduction to the NAG Library CL Interface for further information.
NE_BAD_PARAM
On entry, argument value had an illegal value.
NE_ENUM_INT_2
On entry, trans=value, m=value, pdb=value.
Constraint: if trans=Nag_Trans or Nag_ConjTrans, pdbmax(1,m).
On entry, trans=value, n=value, pdb=value.
Constraint: if trans=Nag_NoTrans, pdbmax(1,n).
On entry, trans=value, pdb=value, m=value.
Constraint: if trans=Nag_NoTrans, pdbmax(1,m).
On entry, trans=value, pdb=value, n=value.
Constraint: if trans=Nag_Trans or Nag_ConjTrans, pdbmax(1,n).
NE_INT
On entry, m=value.
Constraint: m0.
On entry, n=value.
Constraint: n0.
NE_INT_2
On entry, pda=value, m=value.
Constraint: pdamax(1,m).
On entry, pda=value and n=value.
Constraint: pdamax(1,n).
NE_INTERNAL_ERROR
An internal error has occurred in this function. Check the function call and any array sizes. If the call is correct then please contact NAG for assistance.
NE_NO_LICENCE
Your licence key may have expired or may not have been installed correctly.
See Section 8 in the Introduction to the NAG Library CL Interface for further information.

7 Accuracy

The BLAS standard requires accurate implementations which avoid unnecessary over/underflow (see Section 2.7 of Basic Linear Algebra Subprograms Technical (BLAST) Forum (2001)).

8 Parallelism and Performance

Background information to multithreading can be found in the Multithreading documentation.
f16qfc is not threaded in any implementation.

9 Further Comments

None.

10 Example

This example copies a 4×3 real general matrix A to the matrix B.

10.1 Program Text

Program Text (f16qfce.c)

10.2 Program Data

Program Data (f16qfce.d)

10.3 Program Results

Program Results (f16qfce.r)