e01znc evaluates the multidimensional interpolating function generated by
e01zmc and its first partial derivatives.
e01znc takes as input the interpolant
,
of a set of scattered data points
, for
, as computed by
e01zmc, and evaluates the interpolant and its first partial derivatives at the set of points
, for
.
e01znc must only be called after a call to
e01zmc.
e01znc is derived from the new implementation of QS3GRD described by
Renka (1988). It uses the modification for high-dimensional interpolation described by
Berry and Minser (1999).
Berry M W, Minser K S (1999) Algorithm 798: high-dimensional interpolation using the modified Shepard method ACM Trans. Math. Software 25 353–366
Renka R J (1988) Algorithm 661: QSHEP3D: Quadratic Shepard method for trivariate interpolation of scattered data ACM Trans. Math. Software 14 151–152
Computational errors should be negligible in most practical situations.
Background information to multithreading can be found in the
Multithreading documentation.
Please consult the
X06 Chapter Introduction for information on how to control and interrogate the OpenMP environment used within this function. Please also consult the
Users' Note for your implementation for any additional implementation-specific information.
This program evaluates the function (in six variables)
at a set of randomly generated data points and calls
e01zmc to construct an interpolating function
. It then calls
e01znc to evaluate the interpolant at a set of points on the line
, for
. To reduce the time taken by this example, the number of data points is limited. Increasing this value to the suggested minimum of
improves the interpolation accuracy at the expense of more time.