Commutator Properties for Periodic Splines
نویسندگان
چکیده
Commutator properties are established for periodic smoothest splines (on uniform meshes) operated on by certain pseudo-diierential operators. The commutation involves the operations of multiplication by a smooth function, and application of the operator of orthogonal projection onto a spline space; or the orthogonal projection is replaced by a discrete version of orthogonal projection obtained by using a quadrature rule (which need integrate only constants exactly) to approximate the inner product. The results generalise a well known super-approximation property of splines multiplied by smooth functions.
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