nag_conjugate_complex (c06gcc) (PDF version)
c06 Chapter Contents
c06 Chapter Introduction
NAG Library Manual

NAG Library Function Document

nag_conjugate_complex (c06gcc)

+ Contents

    1  Purpose
    7  Accuracy

1  Purpose

nag_conjugate_complex (c06gcc) forms the complex conjugate of a sequence of n  data values.

2  Specification

#include <nag.h>
#include <nagc06.h>
void  nag_conjugate_complex (Integer n, double y[], NagError *fail)

3  Description

This is a utility function for use in conjunction with nag_fft_complex (c06ecc) to calculate inverse discrete Fourier transforms.

4  References

None.

5  Arguments

1:     nIntegerInput
On entry: n , the number of data values.
Constraint: n1 .
2:     y[n]doubleInput/Output
On entry: y[j]  must contain the imaginary part of the j th data value, for 0 j n - 1 .
On exit: these values are negated.
3:     failNagError *Input/Output
The NAG error argument (see Section 3.6 in the Essential Introduction).

6  Error Indicators and Warnings

NE_INT_ARG_LT
On entry, n=value.
Constraint: n1.

7  Accuracy

Exact.

8  Parallelism and Performance

Not applicable.

9  Further Comments

The time taken is negligible.

10  Example

This program reads in a sequence of complex data values and prints their inverse discrete Fourier transform as computed by calling nag_conjugate_complex (c06gcc), followed by nag_fft_complex (c06ecc) and nag_conjugate_complex (c06gcc) again.

10.1  Program Text

Program Text (c06gcce.c)

10.2  Program Data

Program Data (c06gcce.d)

10.3  Program Results

Program Results (c06gcce.r)


nag_conjugate_complex (c06gcc) (PDF version)
c06 Chapter Contents
c06 Chapter Introduction
NAG Library Manual

© The Numerical Algorithms Group Ltd, Oxford, UK. 2014