NAG CL Interface
e01tlc (dim4_​scat_​shep_​eval)

1 Purpose

2 Specification

3 Description

4 References

5 Arguments

1: $\mathbf{m}$ – Integer Input

On entry: must be the same value supplied for argument m in the preceding call to e01tkc.

Constraint: $\mathbf{m}\ge 16$.

2: $\mathbf{x}\left[4\times \mathbf{m}\right]$ – const double Input

Note: the coordinates of $x_r$ are stored in $\mathbf{x}\left[\left(r-1\right)\times 4\right]\dots \mathbf{x}\left[\left(r-1\right)\times 4+3\right]$.

On entry: must be the same array supplied as argument x in the preceding call to e01tkc. It must remain unchanged between calls.

3: $\mathbf{f}\left[\mathbf{m}\right]$ – const double Input

On entry: must be the same array supplied as argument f in the preceding call to e01tkc. It must remain unchanged between calls.

4: $\mathbf{iq}\left[2\times \mathbf{m}+1\right]$ – const Integer Input

On entry: must be the same array returned as argument iq in the preceding call to e01tkc. It must remain unchanged between calls.

5: $\mathbf{rq}\left[15\times \mathbf{m}+9\right]$ – const double Input

On entry: must be the same array returned as argument rq in the preceding call to e01tkc. It must remain unchanged between calls.

6: $\mathbf{n}$ – Integer Input

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

Constraint: $\mathbf{n}\ge 1$.

7: $\mathbf{xe}\left[4\times \mathbf{n}\right]$ – const double Input

Note: the $(i,j)$th element of the matrix is stored in $\mathbf{xe}\left[(j-1)\times 4+i-1\right]$.

On entry: $\mathbf{xe}\left[\left(\mathit{r}-1\right)\times 4\right],\dots ,\mathbf{xe}\left[\left(\mathit{r}-1\right)\times 4+3\right]$ must be set to the evaluation point ${\mathbf{x}}_{\mathit{i}}$, for $\mathit{i}=1,2,\dots ,n$.

8: $\mathbf{q}\left[\mathbf{n}\right]$ – double Output

On exit: $\mathbf{q}\left[\mathit{i}-1\right]$ contains the value of the interpolant, at ${\mathbf{x}}_{\mathit{i}}$, for $\mathit{i}=1,2,\dots ,n$. If any of these evaluation points lie outside the region of definition of the interpolant the corresponding entries in q are set to an extrapolated approximation, and e01tlc returns with $\mathbf{fail}\mathbf{.}\mathbf{code}=$ NE_BAD_POINT.

9: $\mathbf{qx}\left[4\times \mathbf{n}\right]$ – double Output

Note: the $(i,j)$th element of the matrix is stored in $\mathbf{qx}\left[(j-1)\times 4+i-1\right]$.

On exit: $\mathbf{qx}\left[\left(i-1\right)\times 4+j-1\right]$ contains the value of the partial derivatives with respect to ${\mathbf{x}}_j$ of the interpolant $Q\left(\mathbf{x}\right)$ at ${\mathbf{x}}_{\mathit{i}}$, for $\mathit{i}=1,2,\dots ,n$, and for each of the four partial derivatives $j=1,2,3,4$. If any of these evaluation points lie outside the region of definition of the interpolant, the corresponding entries in qx are set to extrapolated approximations to the partial derivatives, and e01tlc returns with $\mathbf{fail}\mathbf{.}\mathbf{code}=$ NE_BAD_POINT.

10: $\mathbf{fail}$ – 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_BAD_POINT

On entry, at least one evaluation point lies outside the region of definition of the interpolant. At such points the corresponding values in q and qx contain extrapolated approximations. Points should be evaluated one by one to identify extrapolated values.

NE_INT

On entry, $\mathbf{m}=⟨\mathit{\text{value}}⟩$.
Constraint: $\mathbf{m}\ge 16$.

On entry, $\mathbf{n}=⟨\mathit{\text{value}}⟩$.
Constraint: $\mathbf{n}\ge 1$.

NE_INT_ARRAY

On entry, values in iq appear to be invalid. Check that iq has not been corrupted between calls to e01tkc and e01tlc.

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.

NE_REAL_ARRAY

On entry, values in rq appear to be invalid. Check that rq has not been corrupted between calls to e01tkc and e01tlc.

7 Accuracy

8 Parallelism and Performance

9 Further Comments

10 Example

10.1 Program Text

10.2 Program Data

10.3 Program Results