Software Listing of Author : "Nick Higham"
- Arbitrary real power of a matrix by Schur-Pade algorithm
- License: Shareware
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X = POWERM_PADE(A,P) computes the P'th power X of the matrix A, for arbitrary real P and A with no nonpositive real eigenvalues, by the Schur-Pade algorithm. [X,NSQ,M] = POWERM_PADE(A, P) returns the number NSQ of matrix square roots computed and the degree M of the Pade approximant used. If A is singular or has any eigenvalues on the negative real axis, a warning message is printed. Function TEST.M runs a simple test of the codes. Details on the underlying algorithms can be found in N. J. Higham and L. Lin. A Schur--Pade algorithm for fractional powers of a matrix. MIMS EPrint 2010.91, Manchester Institute for Mathematical Sciences, The University of Manchester, UK, Oct. 2010; revised Feb. 2011. http://eprints.ma.man.ac.uk/1589/
- Publisher: Nick Higham
- Date Released: 14-05-2013
- Download Size: 10 KB
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- Platform: Matlab, Scripts
- Matrix exponential times a vector
- License: Shareware
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This submission contains two functions for computing EXPM(t*A)*b without explicitly forming EXPM(t*A), where A is an n-by-n matrix and b is an n-by-1 vector. This is the problem of computing the action of the matrix exponential on a vector. EXPMV(t,A,B, computes EXPM(t*A)*B, while EXPMV_TSPAN(A,b,t0,tmax,q) computes EXPM(t*A)*b for q+1 >= 2 equally spaced values of T between T0 and TMAX. The functions work for any matrix A, and use just matrix-vector products with A and A^*. Function TEST.M runs a simple test of the codes. Details on the underlying algorithms can be found in A. H. Al-Mohy and N. J. Higham. Computing the action of the matrix exponential, with an application to exponential integrators. MIMS EPrint 2010.30, The University of Manchester, 2010; to appear in SIAM J. Sci. Comput. http://eprints.ma.man.ac.uk/1536/
- Publisher: Nick Higham
- Date Released: 14-01-2013
- Download Size: 10 KB
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- Platform: Matlab, Scripts
- The Matrix Computation Toolbox
- License: Shareware
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The Matrix Computation Toolbox is a collection of MATLAB M-files containing functions for constructing test matrices, computing matrix factorizations, visualizing matrices, and carrying out direct search optimization. Various other miscellaneous functions are also included. This toolbox supersedes the author's earlier Test Matrix Toolbox (final release 1995). The toolbox was developed in conjunction with the book Accuracy and Stability of Numerical Algorithms (SIAM, Second edition, August 2002, xxx+680 pp.). A demonstration of the toolbox is provided by the script mctdemo. More details on the toolbox can be found at http://www.ma.man.ac.uk/~higham/mctoolbox
- Publisher: Nick Higham
- Date Released: 04-01-2013
- Download Size: 543 KB
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- Platform: Matlab, Scripts
- The Matrix Function Toolbox
- License: Shareware
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The Matrix Function Toolbox is a MATLAB toolbox connected with functions of matrices. It is associated with the book Functions of Matrices: Theory and Computation and contains implementations of many of the algorithms described in the book. The book is the main documentation for the toolbox. The toolbox is intended to facilitate understanding of the algorithms through MATLAB experiments, to be useful for research in the subject, and to provide a basis for the development of more sophisticated implementations. The codes are "plain vanilla" versions; they contain the core algorithmic aspects with a minimum of inessential code. In particular, the following features should be noted. * The codes have little error checking of input arguments. * The codes do not print intermediate results or the progress of an iteration. * For the...
- Publisher: Nick Higham
- Date Released: 08-04-2013
- Download Size: 41 KB
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- Platform: Matlab, Scripts

