NAG Library Routine Document

x10cj_a1w_f (callback_read_type_a1w)

1

Purpose

2

Specification

3

Description

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References

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Arguments

1:     $\mathbf{cb\_handle}$ – Type (c_ptr)Input/Output

On entry: will contain a handle to the callback data object.

On exit: will contain a handle to the updated callback data object, with data item removed from data stack.

2:     $\mathbf{xa}$ – Type (nagad_a1w_w_rtype)Output

On exit: an object of the type nagad_a1w_w_rtype, $x_a$, to be extracted from the callback data object.

3:     $\mathbf{ifail}$ – IntegerInput/Output

On entry: ifail must be set to $0$, $-1\text{ or }1$. If you are unfamiliar with this argument you should refer to Section 3.4 in How to Use the NAG Library and its Documentation for details.

For environments where it might be inappropriate to halt program execution when an error is detected, the value $-1\text{ or }1$ is recommended. If the output of error messages is undesirable, then the value $1$ is recommended. Otherwise, if you are not familiar with this argument, the recommended value is $0$. When the value $-\mathbf{1}\text{ or }\mathbf{1}$ is used it is essential to test the value of ifail on exit.

On exit: $\mathbf{ifail}=\mathbf{0}$ unless the routine detects an error or a warning has been flagged (see Section 6).

6

Error Indicators and Warnings

$\mathbf{ifail}=1$

On entry, cb_handle does not define a valid handle to a NAG AD callback data object. It has not been initialized or has been corrupted.

$\mathbf{ifail}=-99$

An unexpected error has been triggered by this routine. Please contact NAG.

See Section 3.9 in How to Use the NAG Library and its Documentation for further information.

$\mathbf{ifail}=-399$

Your licence key may have expired or may not have been installed correctly.

See Section 3.8 in How to Use the NAG Library and its Documentation for further information.

$\mathbf{ifail}=-999$

Dynamic memory allocation failed.

See Section 3.7 in How to Use the NAG Library and its Documentation for further information.

7

Accuracy

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Parallelism and Performance

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Further Comments

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Example