naginterfaces.library.interp.dim3_​scat_​shep_​eval

naginterfaces.library.interp.dim3_scat_shep_eval(x, y, z, f, iq, rq, u, v, w)[source]

dim3_scat_shep_eval evaluates the three-dimensional interpolating function generated by dim3_scat_shep() and its first partial derivatives.

For full information please refer to the NAG Library document for e01th

https://www.nag.com/numeric/nl/nagdoc_28.6/flhtml/e01/e01thf.html

Parameters
xfloat, array-like, shape

, , , and must be the same values as were supplied in the preceding call to dim3_scat_shep().

yfloat, array-like, shape

, , , and must be the same values as were supplied in the preceding call to dim3_scat_shep().

zfloat, array-like, shape

, , , and must be the same values as were supplied in the preceding call to dim3_scat_shep().

ffloat, array-like, shape

, , , and must be the same values as were supplied in the preceding call to dim3_scat_shep().

iqint, array-like, shape

Must be unchanged from the value returned from a previous call to dim3_scat_shep().

rqfloat, array-like, shape

Must be unchanged from the value returned from a previous call to dim3_scat_shep().

ufloat, array-like, shape

, , must be set to the evaluation point , for .

vfloat, array-like, shape

, , must be set to the evaluation point , for .

wfloat, array-like, shape

, , must be set to the evaluation point , for .

Returns
qfloat, ndarray, shape

contains the value of the interpolant, at , for . If any of these evaluation points lie outside the region of definition of the interpolant the corresponding entries in are set to an extrapolated approximation, and dim3_scat_shep_eval returns with = 3.

qxfloat, ndarray, shape

, , contains the value of the partial derivatives of the interpolant at , for . If any of these evaluation points lie outside the region of definition of the interpolant, the corresponding entries in , and are set to extrapolated approximations to the partial derivatives, and dim3_scat_shep_eval returns with = 3.

qyfloat, ndarray, shape

, , contains the value of the partial derivatives of the interpolant at , for . If any of these evaluation points lie outside the region of definition of the interpolant, the corresponding entries in , and are set to extrapolated approximations to the partial derivatives, and dim3_scat_shep_eval returns with = 3.

qzfloat, ndarray, shape

, , contains the value of the partial derivatives of the interpolant at , for . If any of these evaluation points lie outside the region of definition of the interpolant, the corresponding entries in , and are set to extrapolated approximations to the partial derivatives, and dim3_scat_shep_eval returns with = 3.

Raises
NagValueError
(errno )

On entry, is too small: .

(errno )

On entry, is too small: .

(errno )

On entry, .

Constraint: .

(errno )

On entry, .

Constraint: .

(errno )

On entry, values in appear to be invalid. Check that has not been corrupted between calls to dim3_scat_shep() and dim3_scat_shep_eval.

(errno )

On entry, values in appear to be invalid. Check that has not been corrupted between calls to dim3_scat_shep() and dim3_scat_shep_eval.

Warns
NagAlgorithmicWarning
(errno )

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

Notes

dim3_scat_shep_eval takes as input the interpolant of a set of scattered data points , for , as computed by dim3_scat_shep(), and evaluates the interpolant and its first partial derivatives at the set of points , for .

dim3_scat_shep_eval must only be called after a call to dim3_scat_shep().

This function is derived from the function QS3GRD described by Renka (1988).

References

Renka, R J, 1988, Algorithm 661: QSHEP3D: Quadratic Shepard method for trivariate interpolation of scattered data, ACM Trans. Math. Software (14), 151–152