Polya Conditions for Multivariate Birkhoff Interpolation: from General to Rectangular Sets of Nodes
نویسندگان
چکیده
Polya conditions are certain algebraic inequalities that regular Birkhoff interpolation schemes must satisfy, and they are useful in deciding if a given scheme is regular or not. Here we review the classical Polya condition and then we show how it can be strengthened in the case of rectangular nodes.
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