Toolbox for Grassmann Manifold Computations
نویسنده
چکیده
This a description and user guide for an object oriented toolbox written in matlab for computations defined on Grassmann manifolds and products of Grassmann manifolds. It implements basic operations as geodesic movement and parallel transport of tangent vectors. 1 Content of toolbox There are two classes: • @grass — Contains functions, methods and operations for objects on one Grssmannian. • @prodGrass — Contains the very same functions and methods as @grass but for objects defined on a product of Grassmannians. This class is build on top of the @grass-class. Both classes contain the following functions: File name Short description display.m Displays some information about the object. get.m Gets/extracts various data from the object. innerProd.m Computes the inner product between two tangent vectors. move.m Moves the current point and/or parallel transports tangent vectors. norm.m Computes the norm of a tangent vector. set.m Sets/initiates various data-fields of the object. In addition each class has an object constructor file grass.m and prodGrass.m. The toolbox is available at http://www.mai.liu.se/~besav/soft.html. To use the toolbox download the zip-file, unpack it and make sure to add the folder in the ”matlab search path” (File → Set Path...). I am assuming the reader has the necessary theoretical knowledge about manifolds and various operations on manifolds. Otherwise consider e.g. [2, 1, 3, 4].
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