nag_dge_copy (f16qfc) (PDF version)
f16 Chapter Contents
f16 Chapter Introduction
NAG C Library Manual

NAG Library Function Document

nag_dge_copy (f16qfc)

+ Contents

    1  Purpose
    7  Accuracy

1  Purpose

nag_dge_copy (f16qfc) copies a real general matrix.

2  Specification

#include <nag.h>
#include <nagf16.h>
void  nag_dge_copy (Nag_OrderType order, Nag_TransType trans, Integer m, Integer n, const double a[], Integer pda, double b[], Integer pdb, NagError *fail)

3  Description

nag_dge_copy (f16qfc) performs the matrix-copy operation
BA   or   BAT
where A and B are m by n real rectangular matrices.

4  References

The BLAS Technical Forum Standard (2001)

5  Arguments

1:     orderNag_OrderTypeInput
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 in the Essential Introduction for a more detailed explanation of the use of this argument.
Constraint: order=Nag_RowMajor or Nag_ColMajor.
2:     transNag_TransTypeInput
On entry: specifies the operation to be performed.
trans=Nag_Trans or Nag_ConjTrans
Constraint: trans=Nag_NoTrans, Nag_Trans or Nag_ConjTrans.
3:     mIntegerInput
On entry: m, the number of rows of the matrix A.
Constraint: m0.
4:     nIntegerInput
On entry: n, the number of columns of the matrix A.
Constraint: n0.
5:     a[dim]const doubleInput
Note: the dimension, dim, of the array a must be at least
  • max1,pda×n when order=Nag_ColMajor;
  • max1,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 by n general matrix A.
6:     pdaIntegerInput
On entry: the stride separating row or column elements (depending on the value of order) of the matrix A in the array a.
Constraint: pdamax1,m.
7:     b[dim]doubleOutput
Note: the dimension, dim, of the array b must be at least
  • max1,pdb×n when trans=Nag_NoTrans and order=Nag_ColMajor;
  • max1,m×pdb when trans=Nag_NoTrans and order=Nag_RowMajor;
  • max1,pdb×m when trans=Nag_Trans or Nag_ConjTrans and order=Nag_ColMajor;
  • max1,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 by k if trans=Nag_NoTrans, or k by n otherwise.
8:     pdbIntegerInput
On entry: the stride separating row or column elements (depending on the value of order) of the matrix B in the array b.
  • if trans=Nag_NoTrans, pdbmax1,m;
  • if trans=Nag_Trans or Nag_ConjTrans, pdbmax1,n.
9:     failNagError *Input/Output
The NAG error argument (see Section 3.6 in the Essential Introduction).

6  Error Indicators and Warnings

Dynamic memory allocation failed.
On entry, argument value had an illegal value.
On entry, trans=value, pdb=value, m=value.
Constraint: if trans=Nag_NoTrans, pdbmax1,m.
On entry, trans=value, pdb=value, n=value.
Constraint: if trans=Nag_Trans or Nag_ConjTrans, pdbmax1,n.
On entry, m=value.
Constraint: m0.
On entry, n=value.
Constraint: n0.
On entry, pda=value, m=value.
Constraint: pdamax1,m.
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.

7  Accuracy

The BLAS standard requires accurate implementations which avoid unnecessary over/underflow (see Section 2.7 of The BLAS Technical Forum Standard (2001)).

8  Further Comments


9  Example

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

9.1  Program Text

Program Text (f16qfce.c)

9.2  Program Data

Program Data (f16qfce.d)

9.3  Program Results

Program Results (f16qfce.r)

nag_dge_copy (f16qfc) (PDF version)
f16 Chapter Contents
f16 Chapter Introduction
NAG C Library Manual

© The Numerical Algorithms Group Ltd, Oxford, UK. 2012