Revision 1110 trunk/src/df1b2separable/expm.cpp
expm.cpp (revision 1110)  

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/* 
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* $Id$ 
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* 
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* Authors: Anders Nielsen <anders@nielsensweb.org> and Casper W. Berg <cbe@aqua.dtu.dk>


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* Copyright (c) 20082012 Regents of the University of California


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* Authors: Anders Nielsen <anders@nielsensweb.org> and Casper W. Berg <cbe@aqua.dtu.dk> 

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* Copyright (c) 20082012 Regents of the University of California 

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*/ 
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/** 
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* \file 
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* Matrix exponential function for df1b2_matrix.


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* Matrix exponential function for df1b2_matrix. 

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*/ 
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#include <df1b2fun.h> 
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/** 
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\ingroup matop 
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Matrix exponential.


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Matrix exponential. 

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The matrix exponential is calculated using the Pade approximation adapted from Moler, Cleve; Van Loan, Charles F. (2003), "Nineteen Dubious Ways to Compute the Exponential of a Matrix, TwentyFive Years Later" 
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The main use of the matrix exponential is to solve linear ordinary differential equation (ODE) systems: 

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The main use of the matrix exponential is to solve linear ordinary differential equation (ODE) systems: 

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\f[ 
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\frac{d}{dt}y(t) = Ay(t)\ , \ \mbox{with } y(0) = y_0 
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\f]


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\f] 

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\item then the solution becomes 
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\f[ 
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y(t) = e^{At}y_0 
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