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这是Yousef Saad编写的矩阵运算的Fortran软件包（A basic tool-kit for sparse matrix computations (Version 2),包含常见的排序

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                         | UNSUPP |
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 This is meant to contain any  subroutine that is not part 
 of SPARSKIT proper (for example preconditioners, iterative 
 solvers, plotting and other tools,...) but which are
 nevertheless provided with the understanding that they may
 not be the best codes around or that there is further work
 needed on them.. 

 CONTRIBUTIONS REQUESTED. 
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		             Current contents:
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SUBDIRECTORY BLAS1
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* blas1.f : includes subroutines:
            dcopy : copies a vector, x, to a vector, y.
            ddot  : dot product of two vectors.
            csscal: scales a complex vector by a real constant.
            cswap : interchanges two vectors.
            csrot : applies a plane rotation.
            cscal : scales a vector by a constant.
            ccopy : copies a vector, x, to a vector, y.
            drotg : construct givens plane rotation.
            drot  : applies a plane rotation.
            dswap : interchanges two vectors.
            dscal : scales a vector by a constant.
            daxpy : constant times a vector plus a vector.
            
SUBDIRECTORY PLOTS
------------------ 

* psgrd.f contains subroutine "psgrid" which plots a symmetric graph.

* texplt1.f contains subroutine "texplt" allows several matrices
  in the same picture by calling texplt several times and exploiting job and
  different shifts.

* texgrid1.f contains subroutine "texgrd" which generates tex commands
  for plotting a symmetric graph associated with a mesh. Allows
  several grids in the same picture by calling texgrd several times and
  exploiting job and different shifts.


 SUBDIRECTORY MATEXP   
 -------------------
 routines related to matrix exponentials. 


* exppro.f    computes w=exp( t A) v   -- + a simple test program rexp.f 
* phipro.f    computes w = phi(At)v, where phi(x)=(1-exp(x))/x;
              Also allows to solve the P.D.E. system y'= A y + b