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arXiv · 0706.0521

A trilinear method for finding null points in a 3D vector space

Andrew L. Haynes·Clare E. Parnell
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Abstract

Null points are important locations in vector fields, such as a magnetic field. A new technique (a trilinear method for finding null points) is presented for finding null points over a large grid of points, such as those derived from a numerical experiment. The method was designed so that the null points found would agree with any fieldlines traced using the commonly used trilinear interpolation. It is split into three parts: reduction, analysis and positioning, which, when combined, provide an efficient means of locating null points to a user-defined sub-grid accuracy. We compare the results of the trilinear method with that of a method based on the Poincare index, and discuss the accuracy and limitations of both methods.

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Andrew L. Haynes, Clare E. Parnell. 2007-06-04. A trilinear method for finding null points in a 3D vector space. https://doi.org/10.1063/1.2756751

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