Off-Knot Spline Interpolation and Constrained Approximation:Some Negative Results,

摘要

Quadratic splines are generated which interpolate a function and its derivative at points midway between alternate pairs of knots,and the error bound is shown to be precisely of order (h sup 2) rather than (h sup 3) as expected. This result is related to best constrained approximation by splines and thence to Galerkin methods for constrained problems. (Author)