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Related papers: A general class of $C^1$ smooth rational splines: …

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In this paper, we investigate $C^2$ super-smoothness of the full $C^1$ cubic spline space on a Powell-Sabin refined triangulation, for which a B-spline basis can be constructed. Blossoming is used to identify the $C^2$ smoothness conditions…

Numerical Analysis · Mathematics 2024-11-11 Jan Grošelj , Hendrik Speleers

In the context of isogeometric analysis, globally $C^1$ isogeometric spaces over unstructured quadrilateral meshes allow the direct solution of fourth order partial differential equations on complex geometries via their Galerkin…

Numerical Analysis · Mathematics 2018-12-24 Mario Kapl , Giancarlo Sangalli , Thomas Takacs

We prove that a general planar NURBS curve parametrization $\phi: [u_0,u_m] \xrightarrow{} C \subset \mathbb{R}^2$ admits an inverse map $\phi^{-1}: C \xrightarrow{} [u_0,u_m]$ defined by rational splines. More specifically, we construct a…

Graphics · Computer Science 2026-05-12 Michelangelo Marsala , Pablo Mazón

Computing occluding contours is a key building block of non-photorealistic rendering, but producing contours with consistent visibility has been notoriously challenging. This paper describes the first general-purpose smooth surface…

Graphics · Computer Science 2023-06-06 Ryan Capouellez , Jiacheng Dai , Aaron Hertzmann , Denis Zorin

Multi-degree splines are smooth piecewise-polynomial functions where the pieces can have different degrees. We describe a simple algorithmic construction of a set of basis functions for the space of multi-degree splines, with similar…

Numerical Analysis · Mathematics 2021-10-19 Hendrik Speleers

Splines over triangulations and splines over quadrangulations (tensor product splines) are two common ways to extend bivariate polynomials to splines. However, combination of both approaches leads to splines defined over mixed triangle and…

Numerical Analysis · Mathematics 2023-07-28 Jan Grošelj , Mario Kapl , Marjeta Knez , Thomas Takacs , Vito Vitrih

A new class of rational parametrization has been developed and it was used to generate a new family of rational functions B-splines $\displaystyle{{\left({}^{\alpha}{\mathbf B}_{i}^{k} \right)}_{i=0}^{k}}$ which depends on an index $\alpha…

Computational Geometry · Computer Science 2018-05-14 Mohamed Allaoui , Aurélien Goudjo

A piecewise Chebyshevian spline space is good for design when it possesses a B-spline basis and this property is preserved under knot insertion. The interest in such kind of spaces is justified by the fact that, similarly as for polynomial…

Numerical Analysis · Mathematics 2021-11-12 Carolina Vittoria Beccari , Giulio Casciola , Lucia Romani

Dynamic NURBS, also called D-NURBS, is a known dynamic version of the nonuniform rational B-spline (NURBS) which integrates free-form shape representation and a physically-based model in a unified framework. More recently, computer aided…

Computational Geometry · Computer Science 2013-03-28 Josildo Pereira da Silva , Antônio Lopes Apolinário Júnior , Gilson A. Giraldi

We present Neural Splines, a technique for 3D surface reconstruction that is based on random feature kernels arising from infinitely-wide shallow ReLU networks. Our method achieves state-of-the-art results, outperforming recent neural…

Computer Vision and Pattern Recognition · Computer Science 2021-05-28 Francis Williams , Matthew Trager , Joan Bruna , Denis Zorin

Using neural networks to solve variational problems, and other scientific machine learning tasks, has been limited by a lack of consistency and an inability to exactly integrate expressions involving neural network architectures. We address…

Machine Learning · Computer Science 2021-10-28 Jonas A. Actor , Andy Huang , Nathaniel Trask

This work introduces a scaffolding framework to compactly parametrise solid structures with conforming NURBS elements for isogeometric analysis. A novel formulation introduces a topological, geometrical and parametric subdivision of the…

Computational Geometry · Computer Science 2022-06-10 Stefano Moriconi , Parashkev Nachev , Sebastien Ourselin , M. Jorge Cardoso

Isogeometric analysis is a powerful paradigm which exploits the high smoothness of splines for the numerical solution of high order partial differential equations. However, the tensor-product structure of standard multivariate B-spline…

Numerical Analysis · Mathematics 2023-02-01 Cesare Bracco , Carlotta Giannelli , Mario Kapl , Rafael Vázquez

We formulate as an inverse problem the construction of sparse parametric continuous curve models that fit a sequence of contour points. Our prior is incorporated as a regularization term that encourages rotation invariance and sparsity. We…

Image and Video Processing · Electrical Eng. & Systems 2022-06-28 Icíar Lloréns Jover , Thomas Debarre , Shayan Aziznejad , Michael Unser

In today's machine learning world for tabular data, XGBoost and fully connected neural network (FCNN) are two most popular methods due to their good model performance and convenience to use. However, they are highly complicated, hard to…

Methodology · Statistics 2024-10-28 Linwei Hu , Ye Jin Choi , Vijayan N. Nair

This work introduces and analyzes B-spline approximation spaces defined on general geometric domains obtained through a mapping from a parameter domain. These spaces are constructed as sparse-grid tensor products of univariate spaces in the…

Numerical Analysis · Mathematics 2026-03-25 Clément Guillet

A new global basis of B-splines is defined in the space of generalized quadratic splines (GQS) generated by Merrien subdivision algorithm. Then, refinement equations for these B-splines and the associated corner-cutting algorithm are given.…

Numerical Analysis · Mathematics 2025-10-20 Paul Sablonniere

We introduce here a direct method to construct multivariate explicit B-spline bases. B-splines are piecewise polynomials, which are defined on adjacent tetrahedra and which are $C^{r}$ continuous throughout. The $C^{r}$ continuity is…

Numerical Analysis · Mathematics 2014-09-15 R. O. Linger , H. R. N. van Erp , P. H. A. J. M. van Gelder

The design of globally $C^s$-smooth ($s \geq 1$) isogeometric spline spaces over multi-patch geometries is a current and challenging topic of research in the framework of isogeometric analysis. In this work, we extend the recent methods…

Numerical Analysis · Mathematics 2020-08-17 Mario Kapl , Vito Vitrih

The P-splines of Eilers and Marx (1996) combine a B-spline basis with a discrete quadratic penalty on the basis coefficients, to produce a reduced rank spline like smoother. P-splines have three properties that make them very popular as…

Computation · Statistics 2016-05-10 Simon N. Wood