TEST_MATRIX_EXPONENTIAL 
 Matrix Exponential Tests
    
    
    
      TEST_MATRIX_EXPONENTIAL
      is a C++ library which
      contains some simple tests for software that computes the
      matrix exponential function.
    
    
      Formally, for a square matrix A and scalar t, the matrix exponential
      exp(A*t) can be defined as the sum:
      
        exp(A*t) = sum ( 0 <= i < oo ) A^i t^i / i!
      
    
    
      The simplest form of the matrix exponential problem asks for the
      value when t = 1, that is
      
        exp(A) = sum ( 0 <= i < oo ) A^i / i!
      
      Even for this simple case, and for a matrix of small order, it can be quite 
      difficult to compute the matrix exponential accurately.
    
    
      TEST_MATRIX_EXPONENTIAL needs the C8LIB and R8LIB libraries.
    
    
      Licensing:
    
    
      The computer code and data files described and made available on this web page
      are distributed under
      the GNU LGPL license.
    
    
      Languages:
    
    
      TEST_MATRIX_EXPONENTIAL is available in
      a C version and
      a C++ version and
      a FORTRAN90 version and
      a MATLAB version and
      a Python version.
    
    
      Related Data and Programs:
    
    
      
      EXPOKIT,
      a FORTRAN77 library which
      solves various forms of the matrix exponential problem,
      by Roger Sidje.
    
    
      
      MATRIX_EXPONENTIAL,
      a C++ library which
      demonstrates some simple approaches to the problem of computing the
      exponential of a matrix.
    
    
      
      R8LIB,
      a C++ library which
      contains many utility routines using double precision real (R8) arithmetic.
    
    
      
      TEST_MAT,
      a C++ library which
      defines test matrices.
    
    
      Reference:
    
    
      
        - 
          Alan Laub,
          Review of "Linear System Theory" by Joao Hespanha,
          SIAM Review,
          Volume 52, Number 4, December 2010, page 779-781.
         
        - 
          Cleve Moler, Charles VanLoan,
          Nineteen Dubious Ways to Compute the Exponential of a Matrix,
          SIAM Review,
          Volume 20, Number 4, October 1978, pages 801-836.
         
        - 
          Cleve Moler, Charles VanLoan,
          Nineteen Dubious Ways to Compute the Exponential of a Matrix,
          Twenty-Five Years Later,
          SIAM Review,
          Volume 45, Number 1, March 2003, pages 3-49.
         
        - 
          Cleve Moler,
          Cleve's Corner: A Balancing Act for the Matrix Exponential,
          July 23rd, 2012.
         
        - 
          Roger Sidje,
          EXPOKIT: Software Package for Computing Matrix Exponentials,
          ACM Transactions on Mathematical Software,
          Volume 24, Number 1, 1998, pages 130-156.
         
        - 
          Robert Ward,
          Numerical computation of the matrix exponential with accuracy estimate,
          SIAM Journal on Numerical Analysis,
          Volume 14, Number 4, September 1977, pages 600-610.
         
      
    
    
      Source Code:
    
    
      
    
    
      Examples and Tests:
    
    
      
    
    
      List of Routines:
    
    
      
        - 
          C8MAT_EXP_A returns the matrix for a given complex test.
        
 
        - 
          C8MAT_EXP_EXPA returns the "exact" exponential matrix for a given complex test.
        
 
        - 
          C8MAT_EXP_N returns the matrix order for a given complex test.
        
 
        - 
          C8MAT_EXP_STORY prints explanatory text for each complex problem.
        
 
        - 
          C8MAT_EXP_TEST_NUM returns the number of complex tests.
        
 
        - 
          R8MAT_EXP_A returns the matrix for a given real test.
        
 
        - 
          R8MAT_EXP_EXPA returns the "exact" exponential matrix for a given real test.
        
 
        - 
          R8MAT_EXP_N returns the matrix order for a given real test.
        
 
        - 
          R8MAT_EXP_STORY prints explanatory text for each real problem.
        
 
        - 
          R8MAT_EXP_TEST_NUM returns the number of real tests.
        
 
      
    
    
      You can go up one level to 
      the C++ source codes.
    
    
    
      Last modified on 05 March 2013.