SciPy

scipy.interpolate.bisplev

scipy.interpolate.bisplev(x, y, tck, dx=0, dy=0)[source]

Evaluate a bivariate B-spline and its derivatives.

Return a rank-2 array of spline function values (or spline derivative values) at points given by the cross-product of the rank-1 arrays x and y. In special cases, return an array or just a float if either x or y or both are floats. Based on BISPEV from FITPACK.

Parameters :

x, y : ndarray

Rank-1 arrays specifying the domain over which to evaluate the spline or its derivative.

tck : tuple

A sequence of length 5 returned by bisplrep containing the knot locations, the coefficients, and the degree of the spline: [tx, ty, c, kx, ky].

dx, dy : int, optional

The orders of the partial derivatives in x and y respectively.

Returns :

vals : ndarray

The B-spline or its derivative evaluated over the set formed by the cross-product of x and y.

Notes

See bisplrep to generate the tck representation.

References

[R41]Dierckx P. : An algorithm for surface fitting with spline functions Ima J. Numer. Anal. 1 (1981) 267-283.
[R42]Dierckx P. : An algorithm for surface fitting with spline functions report tw50, Dept. Computer Science,K.U.Leuven, 1980.
[R43]Dierckx P. : Curve and surface fitting with splines, Monographs on Numerical Analysis, Oxford University Press, 1993.