NAG CL Interface
s18crc (bessel_​k1_​scaled_​vector)

1 Purpose

2 Specification

3 Description

4 References

5 Arguments

1: $\mathbf{n}$ – Integer Input

On entry: $n$, the number of points.

Constraint: $\mathbf{n}\ge 0$.

2: $\mathbf{x}\left[\mathbf{n}\right]$ – const double Input

On entry: the argument $x_{\mathit{i}}$ of the function, for $\mathit{i}=1,2,\dots ,\mathbf{n}$.

Constraint: $\mathbf{x}\left[\mathit{i}-1\right]>0.0$, for $\mathit{i}=1,2,\dots ,\mathbf{n}$.

3: $\mathbf{f}\left[\mathbf{n}\right]$ – double Output

On exit: $e^{x_i}{K}_1\left(x_i\right)$, the function values.

4: $\mathbf{ivalid}\left[\mathbf{n}\right]$ – Integer Output

On exit: $\mathbf{ivalid}\left[\mathit{i}-1\right]$ contains the error code for $x_{\mathit{i}}$, for $\mathit{i}=1,2,\dots ,\mathbf{n}$.

$\mathbf{ivalid}\left[i-1\right]=0$

No error.

$\mathbf{ivalid}\left[i-1\right]=1$

On entry, $x_i\le 0.0$, $K_1\left(x_i\right)$ is undefined. $\mathbf{f}\left[\mathit{i}-1\right]$ contains $0.0$.

$\mathbf{ivalid}\left[i-1\right]=2$

$x_i$ is too close to zero, as determined by the value of the safe-range parameter X02AMC: there is a danger of causing overflow. $\mathbf{f}\left[\mathit{i}-1\right]$ contains the reciprocal of the safe-range parameter.

5: $\mathbf{fail}$ – 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 $⟨\mathit{\text{value}}⟩$ had an illegal value.

NE_INT

On entry, $\mathbf{n}=⟨\mathit{\text{value}}⟩$.
Constraint: $\mathbf{n}\ge 0$.

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.
See Section 7.5 in the Introduction to the NAG Library CL Interface for further information.

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.

NW_IVALID

On entry, at least one value of x was invalid.
Check ivalid for more information.

7 Accuracy

8 Parallelism and Performance

9 Further Comments

10 Example

10.1 Program Text

10.2 Program Data

10.3 Program Results