The extremal property of quadratic splines interpolating the first derivatives is proved. Quadratic spline smoothing the given values of the first derivative, depending on the knot weights $w_i$ and smoothing parameter $\alpha$, is then studied. The algorithm for computing appropriate parameters of such splines is given and the dependence on the smoothing parameter $\alpha$ is mentioned.
@article{104498, author = {Ji\v r\'\i\ Kobza}, title = {Quadratic splines smoothing the first derivatives}, journal = {Applications of Mathematics}, volume = {37}, year = {1992}, pages = {149-156}, zbl = {0757.65006}, mrnumber = {1149164}, language = {en}, url = {http://dml.mathdoc.fr/item/104498} }
Kobza, Jiří. Quadratic splines smoothing the first derivatives. Applications of Mathematics, Tome 37 (1992) pp. 149-156. http://gdmltest.u-ga.fr/item/104498/
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