NAG FL Interface
e02jff (dim2_​spline_​ts_​evalm)

1 Purpose

2 Specification

3 Description

4 References

5 Arguments

1: $\mathbf{nxeval}$ – Integer Input

On entry: $n_x$, the number of values in the $x$ direction forming the mesh on which the spline is to be evaluated.

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

2: $\mathbf{nyeval}$ – Integer Input

On entry: $n_y$, the number of values in the $y$ direction forming the mesh on which the spline is to be evaluated.

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

3: $\mathbf{xevalm}\left(\mathbf{nxeval}\right)$ – Real (Kind=nag_wp) array Input

On entry: the $\left(x_i\right)$ values forming the mesh on which the spline is to be evaluated.

Constraint: for all $i$, $\mathbf{xevalm}\left(i\right)$ must lie inside, or on the boundary of, the spline's bounding box as determined by e02jdf.

4: $\mathbf{yevalm}\left(\mathbf{nyeval}\right)$ – Real (Kind=nag_wp) array Input

On entry: the $\left(y_j\right)$ values forming the mesh on which the spline is to be evaluated.

Constraint: for all $j$, $\mathbf{yevalm}\left(j\right)$ must lie inside, or on the boundary of, the spline's bounding box as determined by e02jdf.

5: $\mathbf{coefs}\left(*\right)$ – Real (Kind=nag_wp) array Communication Array

Note: the dimension of this array is dictated by the requirements of associated functions that must have been previously called. This array must be the same array passed as argument coefs in the previous call to e02jdf.

On entry: the computed spline coefficients as output from e02jdf.

6: $\mathbf{fevalm}\left(\mathbf{nxeval},\mathbf{nyeval}\right)$ – Real (Kind=nag_wp) array Output

On exit: if $\mathbf{ifail}=\mathbf{0}$ on exit $\mathbf{fevalm}\left(i,j\right)$ contains the computed spline value at $\left(x_i,y_j\right)$.

7: $\mathbf{iopts}\left(*\right)$ – Integer array Communication Array

Note: the dimension of this array is dictated by the requirements of associated functions that must have been previously called. This array must be the same array passed as argument iopts in the previous call to e02zkf.

On entry: the contents of the array must not have been modified either directly or indirectly, by a call to e02zkf, between calls to e02jdf and e02jff.

8: $\mathbf{opts}\left(*\right)$ – Real (Kind=nag_wp) array Communication Array

Note: the dimension of this array is dictated by the requirements of associated functions that must have been previously called. This array must be the same array passed as argument opts in the previous call to e02zkf.

On entry: the contents of the array must not have been modified either directly or indirectly, by a call to e02zkf, between calls to e02jdf and e02jff.

9: $\mathbf{ifail}$ – Integer Input/Output

On entry: ifail must be set to $0$, $-1$ or $1$ to set behaviour on detection of an error; these values have no effect when no error is detected.

A value of $0$ causes the printing of an error message and program execution will be halted; otherwise program execution continues. A value of $-1$ means that an error message is printed while a value of $1$ means that it is not.

If halting is not appropriate, the value $-1$ or $1$ is recommended. If message printing is undesirable, then the value $1$ is recommended. Otherwise, the value $0$ is recommended. When the value $-\mathbf{1}$ 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

$\mathbf{ifail}=6$

On entry, $\mathbf{nxeval}=〈\mathit{\text{value}}〉$.
Constraint: $\mathbf{nxeval}\ge 1$.

$\mathbf{ifail}=7$

On entry, $\mathbf{nyeval}=〈\mathit{\text{value}}〉$.
Constraint: $\mathbf{nyeval}\ge 1$.

$\mathbf{ifail}=9$

Option arrays are not initialized or are corrupted.

$\mathbf{ifail}=10$

The fitting routine has not been called, or the array of coefficients has been corrupted.

$\mathbf{ifail}=13$

On entry, $\mathbf{xevalm}\left(〈\mathit{\text{value}}〉\right)=〈\mathit{\text{value}}〉$ was outside the bounding box.
Constraint: $〈\mathit{\text{value}}〉\le \mathbf{xevalm}\left(i\right)\le 〈\mathit{\text{value}}〉$ for all $i$.

$\mathbf{ifail}=14$

On entry, $\mathbf{yevalm}\left(〈\mathit{\text{value}}〉\right)=〈\mathit{\text{value}}〉$ was outside the bounding box.
Constraint: $〈\mathit{\text{value}}〉\le \mathbf{yevalm}\left(j\right)\le 〈\mathit{\text{value}}〉$ for all $j$.

$\mathbf{ifail}=-99$

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

See Section 7 in the Introduction to the NAG Library FL Interface for further information.

$\mathbf{ifail}=-399$

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

See Section 8 in the Introduction to the NAG Library FL Interface for further information.

$\mathbf{ifail}=-999$

Dynamic memory allocation failed.

See Section 9 in the Introduction to the NAG Library FL Interface for further information.

7 Accuracy

8 Parallelism and Performance

9 Further Comments

10 Example