The NAG error argument (see Section 7 in the Introduction to the NAG Library CL Interface).
6Error Indicators and Warnings
Dynamic memory allocation failed.
See Section 3.1.2 in the Introduction to the NAG Library CL Interface for further information.
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.
See Section 7.5 in the Introduction to the NAG Library CL Interface for further information.
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.
On entry, .
The function has been called with an argument greater than or equal to in magnitude, for which is not defined.
If and are the relative errors in the argument and result, respectively, then in principle
That is, the relative error in the argument, , is amplified by at least a factor in the result. The equality should hold if is greater than the machine precision ( due to data errors etc.) but if is simply due to round-off in the machine representation then it is possible that an extra figure may be lost in internal calculation round-off.
The behaviour of the amplification factor is shown in the following graph:
The factor is not significantly greater than one except for arguments close to . However, in the region where is close to one, , the above analysis is inapplicable since is bounded by definition, . In this region where arctanh is tending to infinity we have
which implies an obvious, unavoidable serious loss of accuracy near , e.g., if and agree to significant figures, the result for would be correct to at most about one figure.
8Parallelism and Performance
Background information to multithreading can be found in the Multithreading documentation.
s11aac is not threaded in any implementation.
This example reads values of the argument from a file, evaluates the function at each value of and prints the results.